There seem to be problems between the new Gmail contact manager and the one GV uses. One of my friends just got a GV number and I added it manually to his years-old entry in my Gmail contacts as a "Google Voice" phone. I tried SMSing him and got an "Error" message back from GV.
The conversation has an "Add" link by his name. When I click it, enter his name, hit "Create / Add" and then click "Add to" next to his existing entry, I get a duplicate entry with just his phone number. Merging the duplicates using either contact manager (Gmail or GV) causes GV to behave as if it no longer recognizes the number. ("Add" link, no extra info by name, won't show in auto-complete)
What's going on? Has anyone else found similar problems, maybe solutions?
I hope Google's engineers are on this; it has the potential to interfere greatly with the way people use GV and Gmail.
Is this answer to another question applicable?