Update Nov. 14: Double Arrgghh! I discovered I had the Office PDF converter add-on on the machine. No idea why, since I hadn't installed the Office 2007 beta. The component's name didn't start with "Microsoft" like other entries, so watch out. Also, turn on Show Updates to catch everything. Thanks to everyone for suggestions!
I eagerly downloaded the Office 2007 release from MSDN Subscriptions yesterday with great hopes of getting into the new VSTO stuff.
I tried to install it today and (Arrgghh!), the installer complains that it can't proceed because there's some prelease (beta) software on the machine.
The stupid installer error message doesn't specify what it doesn't like (it must know) so I started doing a cleanup in the dark. I did have Expression betas on this machine - but not the Office beta. Uninstalling Expression stuff through the normal process wasn't enough - no luck.
Fellow MVP Patrick Schmid has a page here of manual cleanup steps for the Office 2007 beta. Sure wish this could be automated! Aaron Stebner did a great job on one of those cleanup scripts with a previous VStudio release. (Hint, hint)
Granted, prerelease corruption of a machine is an avocational hazard for bleeding edge risk-takers like me so I don't expect sympathy or product support. That said, in an age of betas, CTPs, and sundry other trial versions, it seems that a prerequisite for any RTM product is a thorough cleanup script that scours the GAC, Registry, file system, and anywhere else that beta debris hides.