New update is out and includes Bluetooth
http://support.apple.com/kb/HT4448?viewlocale=en_US&locale=en_US
Apple TV Software Update 5.2
Feature | Summary |
iTunes in the Cloud | Browse and play your purchased iTunes music directly from iCloud. |
Bluetooth keyboard | Use your Apple Wireless Keyboard to control your Apple TV. See this article for more information. |
AirPlay audio for videos | Send stereo audio from movies, TV shows, and other videos on Apple TV to AirPlay-enabled speakers and devices (including AirPort Express and other Apple TVs). |
Stability and performance | Includes performance and stability improvements with the iTunes Store, AirPlay, Netflix, iTunes Match, and wired Ethernet connections. |