Two fixes were published over the last few days to address issues reported with the Visual Studio 2010 release candidate.
The first fix resolves a crash that can sometimes occur when hovering over an identifier to bring up a tooltip information display. This is a different issue than the crash when bringing up an Intellisense display with an active screen reader that was fixed a few weeks ago.
The second fix addresses an issue with the code files generated by the web forms designer not including certain kinds of web controls in the generated code.
If either issue has been preventing you from trying out Visual Studio 2010, then you should see if the fixes resolve the problem for you.