Are there any major applications out there that are written in C#? By that I mean things that have major performance requirements, say something like PCB design software which could draw hundreds of thousands of geometric primatives per refresh.

I'm asking because I'm sitting in no-mans-land, I have no idea what applications should be written in. It seems that C is seriously becoming a fifth class citizen and accessing the operating system internals is becoming increasingly more difficult, I suspect even more so with the the release of vista around the corner (and down the road, over the bridge and far away ).

I kind of get the feeling that Microsoft themselves don't quite know where they're at. If it seems that C# doesn't cut the mustard when it comes to performance, then what the hell are you supposed to do?

I've played with various GUI toolkits, and everyone I've tried under .NET is unbelieveably slow, conversely the C++ GUI toolkits are fast, snappy and don't have any of the issues I see with the .NET versions.

At the back of my mind I also have cross platform lurking, I pretty much put the cross platform toolkits out of the window because of the clunky "not quite right" interfaces that you end up with. I'd rather implement the backend software in a platform independant library and write GUI code for each platform as required, more effort but you end up with native software.

I know there's probably a few C# gurus on here, so I'd like to have some feedback about this language.

Thanks.

Adrian