After installing SQL Server 2012 SP1 on your workstation, an update to SQL Server Data Tools is required before Visual Studio 2010 SP1 can again open BI projects. You can find the SSDT update links for VS2010 and VS2012 here.
There is also an update for PowerPivot at powerpivot.com for Excel 2010.
I don’t see an update for the Excel 2010 MDS add-in, so that very useful tool may continue to hang and crash as before, unless the problems were actually located elsewhere. We shall see.
I don’t know yet what new features might be found in the new SSDT release. More later if any turn up.
Update (11/13/12): The new VS2012 version of SSDT still appears to lack support for SQL Server 2012 BI projects, which, by the way, is entirely consistent with the SSDT documentation. The new version seems to work about as well as before on VS2010 — no new issues so far.
Update (11/14/12): There is a newer version of the Excel MDS add-in, although it was released months ago. I suspect that the MDM website link for it was not pointing to the same place as the configured link in the MDS Configuration Manager data, although I am really not sure.