The wireless Guitar Hero III guitars for PlayStation 3 will not work seemlessly with the console's Bluetooth technology, instead requiring a dongle that plugs into the USB ports. On the plus side, as noted by Wired's Chris Kohler, is that the dongles are modeled after guitar picks. Much more appealing than a boring, black brick.
Rock Band's wireless PS3 guitar also showed up recently in an FCC filing with a mysterious (albeit less attractive) dongle solution, which presumably will ship with the final product. Maybe by then, however, the Harmonix gang will pretty their dongle up.