I recently installed Office 2010 Plus on new hardware, (HP Pavilion DM1) only to have Word consistently fail on startup. I used, without success, the troubleshooting procedures in:
http://support.microsoft.com/kb/921541
From Safe Mode I disabled each COM add-in, in the process discovering the startup failure ceased when I disabled a Motorola "Send to Bluetooth" add-in. This add-in was not shown in the Reg entry KB921541 had me test.
For what its worth, since I hadn't come across this as a solution to start-up issues.