Julia Lerman points to a list of deprecated APIs in .NET - i.e., ones that will actually leave the next rev of the CLR. This is something that Sun is utterly unwilling to with Java - either at the language level, or at the VM level. It's why I expect that dynamic languages might someday work well on the CLR, while I will be completely astonished if they ever do on the JVM. Microsoft is willing to break a few eggs to make an omelette, while Sun treats each egg as having the worth of gold. That's why the new stuff in Java gets more and more baroque too...