I was about to write a post—a non CTIA, non-cellphone post—about Apple TV hack tutorials over at Tutorial Ninjas. They've got Joost running on an Apple TV, along with a nice collection of useful hacks. Then I noticed they'd put up a post claiming that Apple used the Apple TV's live Internet connection to detect mods and shut down the devices. They've got a handful of confirmations, so it's not definite. But until we find out what's going on, it's probably best to not do anything too tricky to your Apple TV (or just keep it off the Internet).
Pentium chip and OS X make for easy hacking, huh? We should have known it was too good to be true.
Then again, this rumor is unconfirmed. Maybe they broke the Apple TVs using an errant screwdriver or command over SSH. We shall see.
Apple vs Apple TV Hackers [Tutorial Ninjas]