As everyone else I've been following the languages discussion but I still havent build a definite opinion. I think it would be important to understand how much the ability to run managed code from the C/C++ code will be useful in practice. Anyway I hope to see a strong effort to find a common solution, fragmentation is a real and immediate risk.
I strongly feel we should keep very clear the distinction between platform and language. Using different platforms to build the desktop would have a strongly negative impact on usability (because of consistency but even more importantly because of integration) and code sanity. Havoc is addressing it very nicely in his document. When I hear "write once, run everywhere" I start to fear.