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Please help me choosing the language and framework for my undergraduate project [closed]

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I am a final year computer science student from Mumbai University, India.
The topic of our undergraduate project is SOA.
Under this project we are supposed to build 3 service components and one example website that uses those components.
I am quite good with Java and have no experience whatsoever with C# or .NET.
I am having hard time deciding the language and platform for our project.
Can you please suggest what platform I should go for?
Please give me a brief comparison between Java/Java EE and C#.NET/ASP.NET in terms of complexity, ease of development, ease of deployment etc.
Edit:
The original reason why I put this question is:-
We have to do final year project in group of three. My both partners want to do this project in C# and asp.net and I want to do it in java. Since our project is more of server side, java holds some advantages like cross platform over C#
Also this point:-
What if we implement 2 parts in C#.net(which they will build) and 1 part in Java(which i will build) and then use them to build a sample website.
What level(kind) of difficulty it will accompany?

I am quite good with Java and have no experience whatsoever with C# or .NET.
Well then, do you have a particular desire to extend your knowledge into C# and .NET, or do you want to concentrate solely on the actual project.
People can make all sorts of arguments about C# vs Java, but in your case the pertinent facts are that C# will be much better at teaching you a new language, and Java will be much better at not requiring you to learn a new language.
Edit: Following the edit to the question, mixing the languages like you suggest as a possibility has the added advantage of needing you to show how to mix the use of two different languages, which might or might not be useful in itself.

Overall I would say that is is much easier to get started in Asp.NET. With Java EE, just setting a dev environment to do Hello World, can be a lot of work. In Asp.NET, you launch visual studio, create a project, and are ready to go. If you are using Netbeans and Glassfish, then Hello World is no longer a nightmare, but deployment is still a lot trickier.
Architecturally they are pretty similar, Java EE is a bit rustier, but has borrowed from many of the newer ideas of ASP.net.
Once you get up to speed in Java EE, it isn't that bad, so for a long term commercial project, it is a viable choice. For a short term student project it isn't worth the effort, and I would go with ASP.NET, but if I had a choice I wouldn't recommend either platform.
I would build my application in a dynamic language like python, ruby, or maybe groovy. The difference in productivity between static and dynamic languages is huge. Even if all 3 of your team members are new to the language I would expect you accomplish more in less time.
I would recommend looking into the following frameworks: django, pylons, rails, grails. I'm biased towards the python frameworks, but rails is also an excellent choice. Grails is a pretty cool clone of Rails written in groovy, but unless you have to have Java integration, I would stick with the other 3.

I am quite good with Java and have no experience whatsoever with C# or .NET.
If by that you mean you also have experience with building services and site, then use Java, no point in discussing it any further. The only possible reason is if You Want to learn .NET (a great reason imho though), but not at all because you should change to it.
Note that personally I prefer .NET vs. Java, but I would never / ever make a team experienced in Java change to .NET in the scenario you described.
If you do go with .NET, use ASP.NET MVC. It gets you closer to the right skills to learn regardless of the platform / HTML, CSS, JS, HTTP considerations, etc.

What if we implement 2 parts in
C#.net(which they will build) and 1
part in Java(which i will build) and
then use them to build a sample
website. What level(kind) of
difficulty it will accompany?
If the interface between these parts is a widely-accepted standard like SOAP or REST/JSON, then the language the individual components are developed in will matter very little - this is the whole point of such standards, and an important part of the SOA idea as well. I'd even consider such a heterogenous application a better example for what you're supposed to learn.
The only real downside will be that you'll have a harder time helping each other when you encounter problems.

Ill approach this idea by idea:
Platform: You are familiar with Java, I would recommend for the time being staying within Java for the time being.
J2EE do you mean Java EE? J2EE is quite old by today's standards.
There are not many, if any, fundamental differences between .NET and Java platform code. It comes down to a matter of preference and what Operating System you are primarily working on, imo. If it is only Windows development I would lean towards .NET, however if you need portability lean towards Java.
Also I wanted to point out SOA is more of a buzz word consultants use. You will see this as you gain experience in the industry. Cloud is the new SOA, this is purely opinion.

It may be worth your while to do the other components in something you don't know as having that experience could make you more marketable to industry. Look at job offers for a field you'd like to do work in. What experience are they asking for? Maybe use something they ask for as one of your components. I've never seen a job ad that asked solely for Java experience, it's usually accompanied by other technologies like scripting languages and framework experience.

C# popularity industry-wide or is SO atypical? [closed]

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I feel I'm a well rounded programmer, I'm comfortable in C# and java (several large projects with both) but I tend to use C++ for most applications when I have a choice. (and sometimes R,Python, or Perl as appropriate..)
But I am astounded to see the popularity of C# here on SO. There are 18500 C# topics, more than C, C++, and java combined. I've never felt C# as having such an impact in the companies I've worked with but the SO popularity of C# is undeniable.
My question:
Why is C# so popular on Stack Overflow? My question is not so much a SO question as a desire to understand C#'s current acceptance/growth compared to C++ and java.
Possible explanations for the popularity:
C# is truly that popular and accepted in industry, it's everywhere!
SO is not typical, it seems to have attracted a disproportionate number of C# users
C# has more questions/confusions that tend to need community help to solve
Microsoft (maybe on its forums?) encourages people to use SO for questions
The first explanation is likely the reason, but I just haven't felt that popularity in the real world!
What's your reason you discuss C# topics here?

I think the founders of SO are .Net gurus. Most of the people who follow their blogs found out about the site, and started coming here. The original user base was probably pretty .Net/C# focused.
I also think that C# is the preferred language in .Net with it's interop and ability to use old C and C++ code. Those familiar with C, C++, and Java can easily get a useful application built and working in C#, and be pretty certain it will run on any system with the proper .Net framework installed.
And, C# sounds cool.

I wrote about the popularity of C# on another thread, but to discuss why it's popular on SO, I'd say others have the right of it. C# is popular here because most of the people who first came to SO did so following Jeff Attwood's blog. That's certainly how I came here.
The thing is, SO really is language neutral, even if it's written in C#. Both Jeff and Joel have programmed in other languages and are hardly bigots when it comes to language; they just chose C# because it really is an amazing language to program in.
Comparing C# to Java and C++, the growth has been astounding. C# when it was first introduced was basically Java with a better GUI library (Win.Forms beats the ever-lovin' snot out of Swing any day, IMO, and WPF is heads-and-shoulders above both) and a few extra concepts, the biggest of which was delegates and properties as first-class citizens. Since then it's grown meteorically, constantly adding newer and better things. The entire concept of LINQ has drastically changed the way I approach iterations; couple that with WCF for contract-based inter-process/computer communications and WPF for a truly amazing way to build GUIs, and you've got a rock-solid language and library.
Hell, WCF alone makes .NET the correct enterprise/SOA choice.
By contrast, Java hasn't released a new version in, what, 5 years?
C# is innovating. Java is stagnating. C++ is... well let's call it "stable", shall we? The newest version, which is dubbed "C++0x" will soon need to be called "C++1x". The features that are planned require so many changes to the runtime that you're almost going to have Java or C# when you're done anyway so why bother?
Finally, to answer your last question, I come here to answer questions about any topic. I mostly prefer to deal with abstract problems rather than language-specific issues, but I'm always willing to help regardless of language. Just because I love C# doesn't mean it's all I know. :)

I think it's a combination of reasons 2 & 3. From what I've seen, C# is not as popular as Java, and it's probably not as popular as C++.
From where I live, most people use Java, followed by CPP, followed by C#.

Is atypical.
C# is very popular but StackOverFlow is by no means a reflect of the industry-wide.
Dup: Why is there such a large percentage of C# questions?
Related: Why does Ruby seem to have fewer projects than other programming languages?

I've mostly avoided C#, because (a) I've got a silly prejudice about that glandular freak of a program loader masquerading as an operating system — I just don't do Windows, and (b) because it's so much like Java that I have trouble keeping them apart in my head.
That said, there's a lot of C# being done, and if I weren't an old crank it'd probably be a good language.
The thing is that C++ is riding without training wheels. This makes it much better for some things — I helped build the AS/400 operating system in C++, bare metal up — but not as good for the sort of application programming most people do most of the time.

I guess that is partly due to people knowing of the site thru Jeff Atwood's blog, and Joel Spolsky's website.
Although their writings are not technology specific, it has a slant towards MS stack and hence the site is popular among developers working on MS suite of tools/languages.
Once the site becomes more popular and gets ranked high in google for questions on other tools, it will have more questions on those topic as well.

It really just depends if you plan on working with windows. If you like Linux or mac better then you probably want to use another language (although you could use Mono.NET). I just use C# because of 3 main reasons:
Easy to learn
Easy to use
Easy to deploy
But if you like a different language better then use it. Right now I'm learning C so that I can help contribute to some of my favourite open source linux apps.

C++ or Python for C# programmer? [closed]

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I am a corporate C# programmer. I found some time to invest into myself and stumbed upon a dilemma. Where to go from now? C#/.NET is easy to learn, develop for, etc. In future I would want to apply to Microsoft or Google, and want to invest spare time wisely, so what I will learn will flourish in future.
So: Python or C++ for a C# programmer? I am a little scared of C++ because developing anything in it takes ages. Python is easy, but I take it as a child-play language, which still need lots of patching to be some mature development tool/language.
Any C# developers having same dilemma?

I Am a little scared of C++ because developing anything in it takes ages.
I'm not sure how you can say that when you say yourself that you have no experience in the language. C++ is a good tool for some things, Python is good for other things. What you want to do should be driving this decision, not the technology in and of itself.
C# programmer or not, I would assume that you can pick up any language, but a language is just a tool, so your question is difficult to answer.

Python may be easier to get started with, but a dynamically typed scripting language is a very different language from C# or C++. You will learn more about programming learning it than you will by hopping to a close cousin of a language you already know. Really, solid familiarity with at least one scripting language (Python, Perl and Ruby are the favorites) should be a requirement for all programmers.

If you want to apply to Google then Python might be the one to go for, surely MS would like the C# already. If nothing else the competition would not be as fierce as there are much more folk out there with multi years of C++ experience. Also Python gives you a broader language skill and would be a good path to more languages and scripting.
But as said and will be said again, choose your tool wisely and see whether it's a nail or a screw you're trying to secure.

C# is a little closer to Java and C++ than it is to Python, so learn Python first out of the two.
However, my advice would be:
Stick with your current language and learn more techniques, such as a wider range of algorithms, functional programming, design by contract, unit testing, OOAD, etc.
learn C (focus on figuring out pointers, multi-dimensional arrays, data structures like linked lists, and resource management like memory allocation/deallocation, file handles, etc)
learn Assembly (on a modern platform with a flat memory architecture, but doing low-level stuff like talking to hardware or drawing on a canvas)
learn Python or Ruby. Chances are, you'll stick with one of these for a while, knowing all of the above, unless some hot new language has come along by then.

Why not learn some of each. Studying a language for a week or so won't make you an expert, but it will answer a lot of questions in your head and plant a seed for the future.
It's important to not just read through exercises. Find some simple problems that can be programmed in a page or two at most and solve them with each language. That will help you to learn the strengths and weaknesses in the context of the way you think and how you solve problems.

C++ is usually used when speed, and low-level OS access is involved.
It's a good skill to have if you want to expand.
Python allows you to do thing quickly, and it's quite easy to learn, and provides more power than you'd expect from a scripting language, and probably one of the fastest ones out there.
C++ isn't exactly slow to develop, if you've got an IDE, it's not hard to write per-se, but the syntax is going to get you.

If you want to apply to Google and/ or Microsoft then I'd say that of the two you need both!
Given more choice, probably C++ and one other language - either dynamic, functional, or both (Scala might be a good choice too).
It's not necessarily about whether you'd use the languages themselves but more about the different approaches they require and encourage.
If you continue to be "scared" by C++ you're probably going to struggle applying as a dev at either of those organisations - unless you are highly specialised elsewhere.

I think you just asked wrong question. It is not about the tool itself. It should be about what kind of software do you really find enjoying to create. C++ is used in creating different types of applications that are written in C# or Python. Please mind, that C# or .NET itself is not easy to learn. It may be quite easy to develop something that works somehow, but if you just delve into the details...
Anyway, my point is: if you're interested in developing web solutions: go for Python. There is a lot of hype about Python at the moment, and even Microsoft realized the power of this language (you may use your knowledge of .NET and Python programming using IronPython).
C++ is at the moment used in some specific areas. Business apps are written mostly in Java or .NET, and C++ is still great for more low level programming, in areas where performance is the crucial thing (and I mean 'performance' as performance of language/platform itself). The good example is game industry: Java and C# are definitely easier to learn than C++, but... how many 'big games' have been created entirely in C#/Java?
I have another advice for you: if you want to work for Microsoft or Google, do not focus on language itselft. It is NOT the most important thing. Focus on problem solving, algorithms and other stuff (Stevie Yegge's post about how to prepare for an interview at Google).
Oh, and of course as a fan of C++ (and C# too) I must admit that it is not true, that developing anything in C++ takes ages. You probably think of C++ as of "C with clasees" - take a look at STL, templates, advanced templates, Boost... Somehow all those people working in games industry manage to create better and better games in not so looooong time that takes others to create 'boring and easy' business app in Java/C#.

You might be interested in looking at Windows Powershell. It's the latest scripting technology from Microsoft, built on .NET, and can be extended via C#.
Granted, it's not as portable as C++ or Python, but it would leverage your C#/.NET experience more readily. Otherwise, I would suggest C++ (and possibly C). Microsoft builds a lot more of its products with C/C++ than with Python.

As someone familiar with C# and .NET you should consider IronPython. Python for .NET. This would be a good way to leverage what you know and learn a new dynamic language at the same time.

Django or Ruby on Rails [closed]

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I'm a C#/.NET developer looking to mess around with something completely different - something LAM(*) stackish for building web apps quickly.
I'm thinking either Django or Rails. I kind of like the Python language better and it seems to be more full-featured than Ruby for statistical, scientific and networking (let me know if you think this is wrong). However, the RoR community seems to be much bigger - which might make it a safer bet. Do you think this is important? Anybody have experience with both RoR and Django?
Update: Specifically I'm looking to be able to build a community finance oriented site quickly. There are definitely a lot of Ruby Gems to speed up the process, but I noticed Pinax on the Django side which looks promising.
I know that Python is already fairly popular for financial/mathematical programming. Anyone else have an opinion?
Update 2: Noticed some comments about ASP.NET MVC. I have in fact done pretty significant work with ASP.NET MVC - a LOB app for Medical Equipment Servicing, and I loved it. It is IMHO a much better and more intuitive way to write web apps compared with ASP.NET web forms. But, I'm really looking for a non-.NET development environment to develop some chops in.

I kind of like the Python language
better and it seems to be more
full-featured than Ruby for
statistical, scientific and networking
(let me know if you think this is
wrong).
If you think you'll need libraries like NumPy or SciPy, probably best to stick with python/django. I've struggled to find ruby equivalents.
However, the RoR community seems to be
much bigger
Bigger is of course not going to be better. I've had great experiences with the django community in terms of support, and the pluggable app ecosystem is maturing quite quickly.
I would also add that I find the django documentation to be very easy to follow.

If you want a quick stack check out Sinatra.
Django will make more sense faster. It has awesome routing, simple file structure, nice clean syntax, not a lot of WTF moments, and understandable ORM functionality.
Rails you will have to dive into. You will battle activerecord. You will try to wrap your head around the many facets of a rails application.
I like them both. Try them both out. They don't take that long to get a feel for. You should ultimately base your decision on a per-app basis and factor in which language has better modules/extensions/gems for what you need.

Since your stated preference is Python, I wouldn't hesitate to recommend Django. The documentation available for Django is top-notch, and the community is very helpful. Browse the django-users archives or hang out in IRC for a while and you'll get a good sense of the support available.

I like Django better because it's less magic, with Rails i feel they pushed the convention over configuration principle too far, so i prefer the more explicit nature of Django.

funny... I'm in the same boat, though perhaps I've been looking around for a bit longer.
I came in from MS-land (C# too) and I went with Django, but only after I tinkered around with Google's AppEngine, which re-introduced me to Python. Django is well organized, internally consistent (as far as I could tell), and well supported with a vibrant community. Python is well organized, internally consistent (as far as I can tell), and extremely well supported with an amazing community.
Anyhow, there's more to rapid Python web development than Django. You might want to search for: python wsgi framework. Pylons and TurboGears offer enormous flexibility and focus on "best of breed" components, web2py appears to have a very cool DAL/ORM that I'm itching to dig into, and web.py and werkzeug (amongst others) are minimalistic and don't try to dictate how you should build your app. And if you're sticking with Django, definitely check out the Pinax project - it might help kickstart your development efforts.

I just finished building a small social networking site with Django for a client. I was new to Python and new to Django, but it was one of the most enjoyable development experiences I've had in a while (even with the headaches of being new to a language and framework). And it only took two weeks.
If you're building this for yourself then I would try both Rails and Django (or one of the other frameworks that c.batt mentioned) to see what feels the most comfortable. I ended up choosing Django/Python because I liked the language. It felt clean and efficient, and you can't argue with the speed at which you can get a bare-bones site up and running.
As mentioned previously, Pinax is great. If anything you get a solid base to build on top of. I found that I had to extend parts of it to get exactly what I wanted, and a couple of sections I decided to code from scratch because the changes would get "hacky" to match what I needed. Other parts, however, are perfect. The private messaging was used out of the box, just with some new templates to match the site.

i'm another C#/.net guy with the same itch to tinker. Django is appealing. Though the development is easy and fun, i've heard some stories about deployment and configuration headaches with both Rails and Django (mostly rails). It's not like just throwing an asp.net app at IIS or PHP at Apache. For those things you can set it and forget it. I'd be curious to get c.batt's comments on his/her experince with deploying django.
Lately I've been looking at Grails. It uses Groovy which is ruby like. It's very easy to develop in and you can build apps as fast as Rails but you get access to the Java platform via the JVM which could come in handy. There's a ton of open source java components you could drop into your Grails app, plenty of the types of components you'd be looking for. It's really not like building a java app. So far it does feel like Rails. Good luck.

You are at a point where you cant make a bad choice!
My personal preference is django, but I know for a fact rails is good too.
I think the best answer is what the BFDLs of django themselves say:
Try both, use whichever you like.

Rails is like Bible. Unless you are a Saint, you do not need to understand it and you probably will never understand; all you need to do is to believe in it.

Since you're a seasoned .NET programmer, you really should look at ASP.NET and MVC before turning to Rails and Django, at least if your goal is to get up-and-running quickly. It's always easier to leverage something that you already know in-depth.
I was in a similar situation recently -- I had a project that I wanted to push out on Windows and Unix, and so rather than leveraging what I know well (Ruby/Rails), I jumped ship and gave Groovy on Grails a go. It was a really rewarding experience, and I'm really glad I did a few small projects in Grails, but in the end I had a tiny fraction of the productivity I did in the environment where I had a few years' experience, even after months of hacking away on Grails.
So, pick up Django, Rails, Lift, or whatever you feel like doing -- it will help expand your mind, and give you different ways to look at solving problems. But if you want to get going quickly, use what you know (.NET) on a platform designed for you (MVC).

You express a preference for Python so I'd go with Django - it's a fine framework. My personal preference is for the alternative, but I'm not you and both options are good.
This is mostly a duplicate of https://stackoverflow.com/questions/91846/rails-or-django-or-something-else, btw

Like others suggest, trying both is one good way, but really, to me, I would base it more on which language you prefer to use. Sure, if it's a web app, you'll do a lot with the framework, but "every" line of code you write will be in that language. Since both frameworks are strong, it's really more a matter of what language you'll be happiest writing code in, day in and day out.
I personally use Rails and love it, but have many friends using Django. When we discuss things, time and again, it boils down more to language than framework. The languages are fairly different, and you'll typically find one you prefer a lot more than the other, at least in my opinion. I had originally thought Python sounded great, learned it, wrote a few things with it, etc., but it just never "clicked" for me. When I first saw Ruby many years ago it seemed a bit odd, but when I revisited it via Rails, it just felt so natural. When I write code in Ruby I feel like I'm pretty much writing English - if I can think of how I think the code should be written, I can pretty much type that and it works. It just fits my brain better.
Community wise, you'll get a lot of different opinions. I don't think being "too big" means it's bad, nor do I think the Ruby community is by any means "too big", especially compared to say the Java community. Ruby and Rails have certainly gone mainstream to some degree, and for those of us who've worked with it for several years, it seems mainstream, but in the grand scheme of things it's actually still fairly small.
Anyway, good luck, and enjoy looking into them and finding what will delight you to work with.

I'm curious. If you are a C# programmer, why have you ruled out Microsoft's MVC?
You have two different needs expressed in your question:
1) Want to try something new
2) Want to build community finance site quickly.
I understand the desire to look at RoR or Django for need 1, but for need 2 I'd expect you would be more productive more quickly with MVC.
Please note I am not saying that EVERYONE would be more productive more quickly nor am I saying that Microsoft's MVP is inherently more productive, just that someone who is currently a C# programmer would be able to come up to speed more quickly on something that uses C#...

Although I've never tried it personally beyond playing around, you might also want to check out ASP.NET with IronPython. Here's a blog post that details it.

I agree with the people who say: try both and use what you like best.
I think Rails will be an interesting experience because of the convention over configuration and forced MVC architecture. Also, I am not sure what people's experience with Django is on StackOverflow, but all of my Rails questions get answered very quickly.
Also keep in mind that you can call a python service to do some statistical calculations if necessary.
Here is an article written by a guy who went from .NET/C# to Rails to Django/Python, and then back to Rails. Might be worth a quick read.
http://blog.carlmercier.com/2007/01/30/why-i-moved-from-ruby-on-rails-to-pythondjango-and-back/

Your question must be : Python or Ruby ;)

Why would you want to use C# if its slower than C++? [closed]

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I'm looking for a new language to learn after C++ and Java. I was going to try C#, but a bunch of people say its really slow because its a high level language. So why would anybody use C#? Isn't C++ much faster? Does it make development easier, but just have a slower final product?
Also, what can C# be used for? You use it with a lot of .NET stuff on windows, and with ASP.NET, but what are other situations where one would use C#? Will there be a lot of job opportunities for it?

Who exactly is this "bunch of people"? What are they comparing it against?
For the vast majority of things, C++ is not "much faster" than C#. It certainly has benefits in various situations, particularly where you want more deterministic memory handling, but in my experience the bottleneck in most applications isn't in places where C++ would help. As spoulson says, a lot of performance is in the design instead of the exact implementation - and there, it helps to be able to try different designs easily.
Why would we use C# when it's a bit slower than C++? Because it's generally reckoned (i.e. some disagree :) to be a lot easier to develop in without shooting yourself in the foot.
As for what C# can be used for... what do you want to use it for? Unless you want to develop drivers and kernels, it may well be fine for you. (Even OS development has some folks using C#...)
Job opportunities? Loads.
Downsides? Well, .NET itself is only available on Microsoft platforms. There's Mono, but it doesn't have quite the same degree of portability as Java (no doubt another "slow" language according to the same bunch of people).

Code written in assembly can be blazingly fast. Why not just write in assembly?
Don't believe everything you hear. C# has been plenty fast for all my projects. Typically, performance is more a factor of design than raw platform performance.

I'd have to say the people you were talking to simply don't know what they're talking about. Plain and simple.
Many enterprise level applications are built on top of C# and other .Net languages. There is nothing inherently slow about them. Yes the tend to have slower startup times but that's pretty much where it ends.
I noticed you mentioned Java in the list of languages. If you're comfortable with the speed of Java, C# will not present any issues. Generally speaking C# performs at least as well as Java on many different types of bench marks.

My last company was founded by 5 C++ veterans with 15+ years experience each. They spent over a month building a certain Windows service. One of them found and dabbled in C#. Within a week he'd gotten further than the collective had in their month. Shortly after, they all switched to C#.
Why C# if it may perform slower: what price do you put on that degree of rapid development?

Why should it be slow ?
Indeed, C# is compiled to 'Intermediate Language', which is JIT'ed at runtime, but this can give you a performance advantage, since the runtime can generate the most optimized for the platform the code is running on ...
Depending on the application that you want to write, the 'speed' of the language will have a minor impact.
The performance of your application will mostly be determined by the way you design your application, if you make good uses of the tools / technologies you use , etc ...
Sure, C# is not a silver bullet, and there are projects where you shouldn't use it, simply because it is not the right tool for the job, but it will do just fine for most of the business / enterprise app's.

I haven't found many instances where C# isn't a good choice of languages, and .Net (or Mono) isn't a decent platform. Notable exceptions being kernel level development, or drivers. There are plenty of areas where low level, and raw performance is needed. For most, if no all business, or Enterprise applications C# is one of the better choices for development. It's well supported, works with many other systems, libraries, communications channels and components already available not to mention being a fairly nice language (esp. 3.5) to work with.
ASP.Net wasn't a bad platform, I generally find the object/control stack to be one of the short comings for complex interactions. I think ASP.Net MVC fits better for more scalable web based applications. Just the same, it's better than many other systems I've worked with in the past.
In terms of service layers, and even GUI development it's pretty nice. I've got a lot more experience in web based applications, and service/communications/business layers than with desktop GUI applications, so can't comment much there. I feel a lot of GUI development is more about the IDE/Toolkit, than the particular language.
As to slow, you specifically list Java, in most instances, C#/.Net is as fast or faster than Java. IMHO development specifically goes smoother with C# (Visual Studio) over Java (Eclipse). For web-based apps, I like ASP.Net MVC (and even ASP.Net) over Swing. That's just me though.

The people you talked to don't know what they are talking about. C# is a very similar language to Java, all told; it has most of the same benefits and drawbacks. The way it all works is pretty similar (Java/C# is compiled into an intermediate language/bytecode that is interpreted or JIT compiled to native code, with various similar optimizations that you don't need to worry about as a programmer). It's used in a lot of the same situations as Java, and is really aimed for the same market. It's moving a lot faster and bringing in a lot of innovation as a language, but it's (in practice) pretty much Windows-only, if that's a concern of yours. The job market is similar. Both are very popular languages.
As for a language to learn, I would suggest something DIFFERENT. You say you know C++ and Java; C# shouldn't be hard to pick up. Potential employers will know this. Try Scala or Python. Both will give you some new perspectives on things (C# not so much), and make you a better programmer by teaching you new ways to think, rather than just adding another tool to your box.

C# is not always slower - in many cases, it can perform just as well as any language you listed. Usually the algorithm has more to do with the speed than the choice of language.
However, C# is very expressive, and has a great base class library to work with, and super-fast compilation. This means that it's very easy to work with, and can allow you to be much more productive than many other languages, especially C++. For example, I just had a small project that I would have budgeted 1 man-week for in C++, and we finished it up in less than a day in C#, mainly because the base class libraries simplified so many of the tasks.

one big reason to use C# over C++.........look at all those buffer overflow problems that C++ has where people take over your machine because they inject executable code in your strings
or memory leaks....garbage collector is quite handy IMHO

Even if C++ is faster to run, the difference isn't big on today's computers. That's why on mobile devices where cpu and memory are rather limited, C/C++ is still widely used.
But think about development times instead. If it takes 2 months using C++ and 1 month using C#, which would you go for? And when big modifications/refactoring need to be done, a higher level language makes it significantly faster and easier!

I Would definitely use C#. It is actually average speed, and if you liked java, it's almost exactly the same, as they are both based off C++.