2) In what ways is C# ahead of its peers in the industry? I think Async is a great step forward, but it's been in other languages for a while now.
3) He could and he has no impact on VS whatsoever. Scott is essentially a community PM. He talks for a living about stuff. He's a great guy and he's done some good on the web side, but he has no influence on the core of VS.
4) He's actually on the platform, not VS, though he does take a lot of interest in the core component itself. I like ScottGu a lot, I've worked with him a couple of times, but he's driving something very specific (.NET framework and its components).
MS is quite good at building platforms and not nearly as good at building interfaces. A big part of what I did before I left was prove that most people don't understand how to use VS. Moreover, there's a lot you don't see - all of the failed attempts to do things even more amazing than async. While VS itself seems like a model citizen, I would argue that's because it started out as the conglomeration of fairly strong original products and hasn't needed to move too far from where it started to be "best in industry."