Apple has updated the software of its set-top box and “hobby,” the Apple TV. Version 2.2 of the Apple TV software brings both new features (addressing the changes occurring with iTunes) and security fixes. The update is only available through the Apple TV's software update mechanism.

The security enhancements in the 2.2 update address two separate issues, where a maliciously crafted movie file could lead to either unexpected application termination or arbitrary code execution. Both the handling of atom length fields in movie codes and bounds checking of STSZ atoms were improved to resolve these issues. A third issue, where opening a malicious PICT image could cause applications to quit unexpectedly by performing additional validation of PICT images, is also included in the Apple TV update 2.2.

As regards features, Apple has added the following enhancements:

HD TV shows - Purchase the leading HD TV shows directly from the iTunes Store. (US only)

Movie browsing by actor and director - Browse movies on the iTunes store by actor and director. Select “More” on the movie page and browse the actor and director list on the left to see other movies for that individual.

Chapter selection, alternate audio and subtitles - While playing a movie, press and hold Play/Pause to access chapter selection, alternate audio and subtitle display. The display shows the options available for the current movie.

Movie description - Press Up when playing a movie to display a description of that movie.

Genius playlists - To create a Genius playlist based on the currently playing song, press and hold Play/Pause to bring up the contextual menu and select Start Genius. Note: The Genius feature must first be enabled in iTunes 8.0.1 and synced with Apple TV.

On-The-Go playlists - To add the currently playing song to the On-The-Go playlist, press and hold Play/Pause to bring up the contextual menu and select Add To On-The-Go.

Music videos in playlists - Make playlists in iTunes combining your favorite music videos and songs. Play them back on Apple TV and let them play continuously.

Apple TV standby mode - From the main menu, press Play/Pause for about three seconds (or go to Settings > Standby)

According to Apple, some users' set-top boxes may take up to a week to display the update. Therefore, all Apple TV owners are encouraged to download the update manually, using the software update mechanism of the device. Unlike most Apple software updates, this release will not appear in your Mac's Software Update, or on Apple's support / downloads section of the official website.