Just got this in an email from Microsoft:
Greetings from Microsoft Connect!
This notification was generated for feedback item: VS 2010 - Hangs when debugging ASP.Net 3.5 web application or website which you submitted at the Microsoft Connect site.
The fix for this is now available for download and install from https://connect.microsoft.com/VisualStudio/Downloads/DownloadDetails.aspx?DownloadID=30738&wa=wsignin1.0
Visual Studio Debugger
Note: The fix for this issue was packaged with the fix for another issue, the KB article currently only lists the other issue, but this download does contain both fixes
You may receive a general "Feedback Item Updated" notification as well, if any other changes were made by Microsoft.
Thank you for using Microsoft Connect!
the Microsoft Connect Team
more later – joel