On stability side, the new feature appears to be fully functional in the 3rd beta version of iOS 6 allowing users to send audio from any content, including video, wireless to external AirPlay-enabled speakers. Currently, Apple TV using the latest public version of iOS, the 5.1.1, is known to passively receive content via AirPlay. AirPlay existing parameters only allow user to enable or not AirPlay and set a password.
The new update of iOS seems to give the Apple TV more and more features. From a passive media player it become an active content broadcaster. It will now send content to another AirPlay-enabled device. This is good news for us, this kind of new feature makes the device less and less dependent on external device. For example, users can access their music library stored on icloud and use the Apple TV to listen to this music on speakers connected through an AirPort Express.
FlatPanelsHD also give us more tips adding that the current Apple TV being not 5.1 surround sound capable, the Dolby Digital option should be disabled otherwise you will have very low sound. This option is available though the "Audio & Video" options in the Apple TV Settings menu. Do that means perhaps Apple will brought Dolby 5.1 soon to Apple TV ? If it goes through a simple firmware update, that’s very good for us.
On new features side, we can say that with the iOS 6 do extend the Apple TV functions. Besides being able to rearrange the apps icons (like on iPhone or iPad), adding the ability to stream audio to external speakers shows that Apple expects to transform its media player to an active broadcaster. Rumor says that Apple is preparing an app store dedicated to the Apple TV. Let’s see what come.