Forgive me if I'm being stupid, but...
 

I'm looking into new head units for my B5, and there are a few among the ones I'm considering that are Bluetooth ready. In the context of CD head units, is this implying that I can sync my head unit with my cell phone's Bluetooth headset so that if someone calls, the music will pause/mute/etc? Does it mean that I can end up using the stereo system itself as my hands-free device (obviously I'd have to use a microphone mounted in the car to catch my voice, but would it broadcast the caller's voice through the stereo?) Or is there another use for Bluetooth when it comes to CD players in the car? Thanks in advance, and like I said, if I sound dumb here, it's because I've been out of the audio scene for a few years.