I have a 40Gb Apple TV so most of my content is shared from my iMac's iTunes. During a storm last night, the cable went down but I still had power and my local network connection was still alive. I could access the shared content via my MacBook, but the AppleTV wouldn't allow any of the usually shared content. 
Cable down is the ideal time to show off the AppleTV...too bad I could only select a few sync'd programs instead of my full shared library.
Cable down is the ideal time to show off the AppleTV...too bad I could only select a few sync'd programs instead of my full shared library.