According to AppleTVhacks.net, the Broadcom card replaces the AirPort/WiFi card in the AppleTV. So my guess would be to follow the AirPort card replacement guide, and instead of putting in another AirPort card, you put in the Broadcom. Keep in mind that you’ll have to use wired Ethernet to download shows to the AppleTV from that point onwards. The aTV Flash software XBMC edition allows the HD card to work and lets you use services other than iTunes.