The new Apple TV update is labeled build 9A4051, and can now be downloaded directly from the device. The version number would suggest that it is a minor update, fixing issues in the Apple TV version 4.4 software update that accompanied the launch of iOS 5 in October.
Version 4.4.3 marks the third update to have arrived since the release of 4.4, a more significant update that added AirPlay Mirroring support, Wall Street Journal Live, National Hockey League Content, Photo Stream, and iTunes Trailers. Details for Apple TV Software Update 4.4.3 have not yet been revealed by Apple.
The last Apple TV update arrived in late October with Software Update 4.4.2. It addressed an issue that required a small number of Apple TV units to be connected to iTunes in order to complete an update.
Apple also quietly added support for iTunes Match to the Apple TV early this month, without the need for a software update on the device. The $24.99-per-year iTunes Match service, which lets users re-download their entire music library on a range of devices, launched this week with the release of iTunes 10.5.1.