Yesterday, I had a chance to play with a bluetooth headphone that was just announced at CeBit. It supports both audio+headset profile.
(this is a prototype, not a final product)
You can listen to iPod, TV or any audio source with it. It supports BT Class 1, so you can go as far as 30 meter (or even more) from the source of audio and feel no degragation in audio quality.
If you someone call you on your bluetooth cellular phone, you just push a button and it will be your bluetooth headset. You can use it with your Mac to do an iChat AV audio chat.
This thing is so cool!