I had a Droid X and my Kenwood head unit in my car with BT, everything worked very well. My Galaxy Nexus works fine when using the hands free calling but when I stream music over BT with the same head unit I get skips and stutters in the audio. I have tried several things like going into airplane mode repairing the Nexus and I still get the same results. When plugged into the headphone jack it works fine besides Google music player being a big pile of crap winamp works much better. Just checking to see if anyone else is having this issue and if there is any work around.
You can use A2DP Volume to manage the settings when connecting and disconnecting from your cars Bluetooth. It has a feature to disable WiFi when connected to Bluetooth which fixes a known issues that causes music stutter. It can also launch and kill apps based on connection. I captures your cars location automatically as well as several other features. Just search A2DP Volume on Android Market. It is free, open source, and ad free.