Scott Guthrie has a new blog post instructing people how to cleanly uninstall all the Beta 2 bits on a machine before installing the RTM of Visual Studio. This is a great list but if you’re an early adopter like I am beware.
If Beta 2 was your first test build of Visual Studio 2008 (Orcas), you should be good. If you installed Beta 1 or any of the CTP’s, I have found that paving a machine is the only way of really cleaning up some of the crud left by the earlier betas. Beta 2 was very good about cleaning up in an uninstall scenario, but Beta 1 was not (as well as not behaving great side-by-side with VS 2005). It was a beta afterall so no harm no foul. But if you have installed early bits, i’d suggest starting with a clean machine.
On the other hand, if all you have is VS 2005 on your machine, the RTM (like Beta 2) works great side-by-side for those of us who need to keep 2005 sln file compatiility.