I generally agree with Bob Frankston that Bluetooth is troubled. But I did manage to make my first use of Bluetooth yesterday — I sent a picture from my Nokia 3650 to his t68i and it worked amazingly. And then he sent a business card back and it worked.
The #1 way I’d use this would be to transfer entire phonebooks between phones if this was possible. Right now the phones just let you send single contacts at a time, this sucks.