Saw a stealth cheater today. It wasn't the perfect aim that tipped me off- it was the fact that he was totally unaffected by the new movement code (and was strafing/running just a little too fast). Whatever GU11 cheat is currently being passed around completely ignores the "weight" code. And before the whole "all you see is cheaters" business starts up: Cheats, even stealth cheats, are quite rare. I'd say one in a few hundred players is a stealth cheater. Usually when you die to weirdness, it's plain old lag.
now if the performance of the game would allow permanent vid cap, it would be interesting to see a video of your sighting