I have a question to piggyback here:
I'm thinking of setting up an iMac as a PVR-HTPC with a projector (facing the opposite direction), and I'd like to have the wired keyboard and mouse on the desk side but also use a bluetooth mouse and keyboard wirelessly... can you have both plugged in (well, wired plugged in and BT connected), and just suddenly start using the Bluetooth and have it pick up?