I love Fords Sync system with my iPhone 4. You can stereo Bluetooth to it, or in the case of my Edge, there's a USB connector in the center console that you can plug into. Not sure if they've fully implemented A2DP yet, as of 4.0.1 you can't use the cars controls to forward songs, voice control, etc unless your on USB.
For a factory stereo, it's pretty damn awesome!!!