I don't know if this is new to Snow Leopard, but I just paired my Jawbone Bluetooth headset with my Mac Pro desktop as the input/output audio device and it works! Sound quality for playback is not great (I don't think I'll be listening to much music this way), but it sure beats a USB headset for video conferencing and voice dictation. I'll be setting up my MacDictate speech profile now.
Instructions: Basically nothing to it. Turn on Bluetooth on your Mac. Press and hold both buttons on the Jawbone to make it discoverable.