According to numerous TUAW tipsters, Apple TV's authorization servers appear to have been affected this weekend. They have been providing only intermittent access to paid DRM'ed content and Home Sharing features.
Users report error messages preventing them from accessing and playing back content: "Authorization is required. To play this content on your Apple TV, choose Authorize This Computer from the Store menu in iTunes on your computer, then enter the Apple ID and password used for the purchase."
If your Apple TV unit is affected, you are not alone. TUAW has received many user complaints and links to sites where frustrated customers have gathered. Apple's KB support posts do not appear to be helping customers resolve these issues.
Were you affected by this outage? Drop a note into the comments and let us know your situation.