I recently did an in-place upgrade of a TFS 2010 RC to RTM box. All appeared to be going fine, all the verification in the upgrade wizard passed, but when I hit configure the first step failed. It said there was a missing dbo.sysobjects in the warehouse DB. I then had to resort the configuration DB as it was partly upgraded to try again as the DB was left partially upgraded.
I got round this problem by telling the upgrade to ignore the reporting side of TFS. The upgrade completed without issue. I was then able to re-add the reporting via the TFS administration console (optional configuration of features in 2010 is really useful!). I actually chose to recreate the warehouse DBs anew to make sure I was bringing over no corruption. Once TFS had rebuild all the DBs and cubes all was working fine.
So the technical tip: if upgrading TFS 2010 and you are getting a problem with the reporting sub system, consider bypassing the upgraded and just rebuilding that system when you are finished
_[Update 19th May 2010] _
Saw the problem again today on another site going a RC->RTM upgrade. the exact error message you get is
_Exception Message: TF255356: The following error occurred when configuring the Team Foundation databases: Error occurred while executing servicing step Upgrade Warehouse for component Tfs2010WarehouseBeta2ToRTM during Tfs2010Beta2ToRTM: Errors in the metadata manager. The dimension with the name of ‘Work Item Tree’ already exists in the ‘Tfs_Analysis’ database.
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