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Other thank iTunes integration the AppleTV has very little to offer - I have one of the Western Digital Media boxes you linked to and it lays waste to Apples offering, codec support on the WD model is very good and supports 99% of video codecs available to most users [the WD receives fairly regular firmware updates adding extra functionality] I love most Apple products but the AppleTV sucks they need to open up codec support for more widely used/available media instead of locking it into Apples ecosystem. Oh and the WD box plays 1080p media very very well...
 
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