Apple TV input lag?

Has anyone measured the input lag of Airplay Mirroring rigorously?

It feels pretty epic to me, but I've no idea how much of that is due to my TV and don't have a slow motion camera to test it with.

Some googling put it around 200-250ms but there was no mention of how much of that was from the TV set it was connected to, what kind of router was being used, was the ATV wired or wireless. It was also using an iPad 2 and a dev preview of iOS 5 - has it gotten better with iOS 7 and newer iOS devices?

Mostly, I am curious as to how good the Airplay Experience could get, and whether buying a low-lag TV might push airplay gaming over from "totally unplayable" into "just about OK".