Apple TV 2.3 firmware now available

Remember your Apple TV? That thing next to the TiVo? It’s ready for its upgrade. The improvements are very minor but it now supports third-party remote control learning and AirTunes streaming to other audio outputs including Airport Express speakers as well as other Apple TVs. You should be able to download the new firmware in Settings.

AirTunes Streaming from Apple TV Music can be streamed via AirTunes to Airport Express speakers or other Apple TVs in your house.
Third-party Remote Controls Apple TV can now learn other remote controls and use them in addition to the Apple Remote.
Playlists Playlists in iTunes that contain Movies, TV Shows, Podcasts, and Music Videos can now be seen on Apple TV.
Music Volume Control Support for volume control in Music.

via crunchgear.com