自.Net 2.0以来，.Net IL一直在改变吗？

I've heard the claim before that .Net 3.5 made no changes to the IL that it compiles to. Upon thinking through all of the compiler features that I know were introduced, it does, in fact, seem that they could all be implemented in the same old IL, but I can't find an official source to corroborate this claim. Is it true?I've heard the claim before that .Net 3.5 made