We previously reported on a new feature in the AppleTV software version 4.4 which permits a triple-click of the Play button on the AppleTV remote to activate VoiceOver. This information was based on several reports from a couple of sources, but this information was incomplete. After users began noting that it didn’t seem to be working, we tracked down a clarification.
This functionality only works during the AppleTV setup phase. During setup, it will say, "Triple-click Play button to activate VoiceOver". Once the AppleTV is setup, this functionality is no longer available.