The simple answer to your question is YES, if you have Leopard.
Let me explain, I have an iMac with OS X 10.4 Tiger and bought a SONY CMTHX5BT to stream all my iTunes music to. I then found out that Tiger does not support the AVRCP BT protocol. I downloaded a trial version of Audio Gateway by Softick. This allowed me to stream to the SONY. However, there were quite a few pauses during the streaming so I didn't pay $20 for it, I just let it expire. I was hoping to find a different solution. I wasn't sure if the problem was the iMac BT range or the software. Any suggestions from anyone else would be appreciated.
Now about the MBP. I just got a MBP with Leopard last week and the first thing I did was try Leopard and see if it would stream to the SONY which it did. Only problem being, the quality of this stream. Even with the MBP right beside the SONY, the pauses and hiccups were TERRIBLE, very very bad so not impressed so far.
I am now trying to solve both these issues but as I said the simple answer is yes.
I just bought Sony CMT-HX90BTR with bluetooth support. Pairing it with my MacBook Pro having Leopard was really simple. You just have to choose to use the hifi system as a headset. Streaming music from iTunes works great. Sound quality is a bit low though and there are some cracks some times in the beginning of the songs. The quality is absolutely enough in terms of streaming podcasts etc. to your audio system. And you can always plug your iPod into it to reach better quality. Sony CMT-HX90BTR thing rocks even though they could have focus more on usability.