We hear via Crave and confirmed via a quick check at the Apple Store that Apple is discontinuing their Apple-branded Bluetooth headset. It had a nice run, we suppose, but aside from a clever dual-charging iPhone accessory, the headset was actually pretty bare-bones compared with other options (My own personal favorite is the BlueAnt Z9i headset).
It's probably a safe bet that Apple is going to replace it with a set of Stereo Bluetooth headphones in the fairly near future, given that their A2DP implementation on iPhone 3.0 is pretty nice (check out the images in our walkthrough -- much easier to toggle it on the iPhone than it is on most other devices). Another safe bet may be that Apple's 'phones, as with their current headphones and also this now-discontinued Bluetooth headset, will be decent enough but not as good as what you can find from other manufacturers. I'm fond of the Motorola S9-HD, if you're curious, but the Voyager 855 is my day-to-day, as it's sorta-kinda safer while riding my bike as I can leave my left ear open to listen for cars.
[Thanks to all of you who sent this in!]