I too am having the same issue. I watched some Droid videos before I got my Incredible and was excited to have one button to basically operate my phone. Now it only Google Searches and oddly enough works when I say "navigate to ___"
I talked to some of the guys at a Verizon store who have Motorola Droids and would only recently have been updated to 2.1 so they weren't familiar with that and only recently familiar with Voice Search in the first place.
I have my settings set for searchable items and ironically have Internet turned off and yet it still searches Google before anything else.
This would be a HUGE deal if I could have this feature so anybody with information would be greatly appreciated!