Unfortunately, we introduced a regression into Visual Studio 2010 SP1 in the process of fixing a performance issue in the build details view that a number of customers had reported (viewing the log was really slow for larger builds). We made this change late in SP1. I apologize for the inconvenience. I want to make sure you know about that patch if you hit the problem.
The fix is available at http://connect.microsoft.com/VisualStudio/Downloads/DownloadDetails.aspx?DownloadID=34824.
Visual Studio 2010 SP1 crashes or shows the following error when attempting to view a build report on a TFS 2008 server:
"TF50316: The following name is not valid. Verify that the name does not exceed the maximum character limit, only contains valid characters, and is not a reserved name"
Additional Information about the issue resolved by this Hotfix can be found in its Knowledge Base article at http://support.microsoft.com/kb/2522890