I speak only for myself here of course, but what I find so "icky" about C# is not the language, but the development environment. I haven't used the latest VS so it might be better, but even 2007 still felt years behind the popular java IDE's, and there didn't seem to be any real competition to it either. (Someone please correct my missteps here; I'd love to know more about it than I obviously do now.)
I haven't had any issues with clunky Java IDEs since my 256mb ram IBM laptop died.
Visual studio on the other hand lacks so many of the things that made it nice to develop in Java, such as automatic implementation of interfaces, inplace renaming, the ability to move a variable from being inside a method to becoming a field at the click of a few buttons.
That said, C# is light years ahead of Java - too bad that the ide isn't.
I haven't tried VS 2010, but in previous releases there was no "Go to class..." type functionality! How is that easy to navigate? Thank god for JetBrains ReSharper plugin.
All the major Java IDEs have had "Go to class..." for a long time.
Okay, how would you design icons for abstract concepts like struct and interface? About half those icons actually make a lot of sense to me (the other half are just arbitrary symbols, as far as I can tell).
You pick those up in context pretty quickly. If you know a class has a method "DoSomething" and you see the pink block icon next to "DoSomething" and "DoSomethingElse", then you learn pretty quickly that "DoSomethingElse" must be another method.
The problem is that the overwhelming majority of C#/.NET developers ONLY have used Visual Studio. Monodevelop is not quite up to par, so really, for C#, there's only one choice for an IDE outside of notepad... I used to do more java development, but now do more C#, and I miss the the polish of Eclipse over VS (Incremental Java compiler is a huge win, Refactoring (resharper freeze my machine), Search indexes, Auto completion is still better, code navigation via back button, much better Source control integrations...)
I've used VS2005 and VS2008 extensively, and always enjoyed working with them, especially VS2008. I haven't used VS2010 much (read: at all) but am looking forward to using it.
VS2010 is IMO a far superior IDE to VS2008. Especially if you're doing WPF or Silverlight. The browser, project system, and designer is just way faster. Which is pretty surprising because the Beta for VS2010 was horribly slow.
My main ask is to get Xaml in better shape. I know that the dynamic language crowd will love Xaml, because 99% of all errors are runtime exceptions, but that's just a freaking drag on my productivity - especially since I think they can do static analysis to statically find probably 75% of the issues at compile time.
I haven't really used any of the Java IDEs out there, but I thought I'd mention that you probably mean VS2008 ;)
As for Visual Studio, its extensibility model might not be "awesome", but that is definitely changed for the better in VS2010, and for the "rest of us", jetbrains has some pretty decent products.