Viability of C#/.NET as the new standard game dev platform?

Question

For a long time now C++ has been the dominate game development language. Many AAA quality 3D engines are available to fit any budget.

My question is, with the rise of X

Answer 1

Well, between those too I think C#/XNA is a clear winner based on library support and really the maturity given Microsoft's experience in DirectX. That being said, I don't see C#/XNA replacing C++ as the lingua franca of serious 3D game programming (i.e. by large development houses) for a very long time, if ever.