the point is. why should we take the risk?
this is different from some unknown patent that may be infringed by the kernel. this is a well defined piece of software that we can just leave out.
i haven't used C# but is it so much better than, say, Python?
to me it looks like yet another interpreted language. why bother?
What difference does it make? It is a sad fact that virtually every non-trivial application infringes on *some* patent. When things like mouse clicks, scrollbars or "methods that retrieve data from the internet upon user request" can be patented, you understand that the whole system is broken and ridiculous. Hell, even *Microsoft* is asking for patent reform!
Besides, the US is not the whole world (shocking, I know!) Most of us simply *don't care* whether Microsoft holds a freaking .Net patent in the US. (Ok, I lied: we do care, because we want you to use our software. Stop being sissies and fix your patent system! )
Other than that, C# is a JIT-compiled, statically typed, object oriented language with functional capabilities. Python is an interpreted, dynamically typed, multiparadigm language. Pretty different beasts - neither is intrinsically "better" than the other.
But even if they were the same old thing, it still wouldn't matter: developers like C# and create some awesome stuff with it. That's all that counts.