A couple of days ago a customer of the new version MZ-Tools 7.0 for Visual Studio reported a bug regarding the dropdown menus visibility not preserved across Visual Studio sessions. I isolated the bug which happened to be a bug in the WPF-based commandbars of Visual Studio 2010 (and 2012), not happening in VS 2008 and before.
I have written a small article to document it:
BUG: CommandbarPopup.Caption changes CommandbarPopup.CommandBar.Name and viceversa.
http://www.mztools.com/articles/2012/MZ2012007.aspx
And I have reported the bug to Microsoft Connect (currently awaiting to be acknowledged):