Bluetooth headset profiles
I ran into the same problem when I went from a cell phone to a BB at work. My old bluetooth headset didn't have the correct bluetooth profile for streaming music. I am using a Samsung WEP870 now (which the karma gods have seen fit to put a $20 rebate on at Amazon that took effect after I bought it - Go figure).
The headset itself works well.
I think the profile needed to stream music are A2DP (Advance Audio Distribution profile). There is another one called AVRCP (Audio video remote control profile) that allows the bluetooth device to control the playback of music.