But not the .NET libraries! (Score 0)

It looks like Microsoft is only opening up the CLR to the cross-platform world, but so many of the .NET libraries on which applications rely remain closed and windows only. Kinda like if Sun gave us a JVM with no rt.jar chock full of utilities, UI components, and otherwise useful tooling. Don't expect that slick Windows.Forms app you wrote to "just work" when you try it out on Ubuntu.