Just something to note. I had a Bluetooth earpiece (Plantronics 925) and was in a voice call with my wife on her iPhone 4. When I initiated FaceTime and it transitioned over, it dropped the Bluetooth audio and reverted to the onboard speaker and microphone. With FaceTime's simplified GUI, there's nothing to switch the audio back to the headset, and tapping my button on my earpiece did nothing. FYI, I also tried this with wired headphones and the audio continued on the headphones properly (didn't go into speakerphone mode). Looks like Apple doesn't really like, care, or know Bluetooth much or enough to implement AVRCP for controlling playback, or using Bluetooth audio for non telephony purposes.