On my new project we are evaluating using Visual Studio 2010, but still building against .NET 3.5 ... for the time being.
We have been experiencing frequent lockups of the IDE and crashes.
After some investigation I came across a couple of possible reasons:
AnkhSVN version (via Resharper Blog) ... http://blogs.jetbrains.com/dotnet/tag/resharper-51/
Patch for VS2010 Cut and Paste ... http://blogs.msdn.com/b/visualstudio/archive/2010/06/25/patch-available-for-cut-or-copy-displaying-insufficient-memory-error-in-vs-2010.aspx
We are still seeing the odd crash/hang but it has improved the situation a lot.
Hope this is useful for someone.