Yesterday, my wife attempted to BT snyc her new 51v w/ my Cingular 8300 BlackBerry while dining out (okay, we are both geeks - she was once a normal liberal arts major). Both devices recognized one another. We haven't had the time to see whether the voice or data service can be accessed. If so, I'll report back.
Also a warning for those planning to purchase/use an 8300, your current 7200 series soft leather belt clip will not switch the device off when cradling it. RIM has moved the magnetic switch. I cannot tell you how many self dialed calls the unit has made. The worst was a 0400 call to my wife!!