UPDATIER: See this.
UPDATE: Some consideration of whether this is actually a VAC problem, or simply MW2 being a bit nob, can be found here.
We're getting word that over the last week a slew of Modern Warfare 2 players have been banned from the game by Valve's Anti-Cheat software, or
HAL VAC for short. You know, the same software found in Team Fortress 2 and Left 4 Dead 2? The one that issues irrevocable bans that Valve will not remove or discuss "under any circumstances"? Well, a great deal of this freshly-banned crowd are claiming (screaming, really) that they've never cheated. Ever. Making this a bit of a sticky situation.
The angry mob can be found on the Modern Warfare 2 forums, the Steam forums and in their invite-only Steam Group (bearing the cute url extension of youowemesixtydollars). Alternatively, if you're lazy or a fan of very sincere rock'n'roll, here's a YouTube video that collects some of the protesting forum threads in a montage. I particularly like the guy who tries to prove his innocence by posting terrible kill stats from Counter-Strike and pointing out that he sucks and doesn't mind sucking, so why would he cheat?
Valve's support staff have, apparently, been courteously informing people that they're sorry but their hands are tied, which makes sense- if you've got automated software which cuts people off from one of your products, you need to maintain a policy that the software is infallible, otherwise the whole system comes crashing down. This problem they've run into now is compounded by another bit of VAC policy, that of never sharing information on what the cheat was exactly or when it was found. VAC bans often kick in weeks after the software detects the cheat.
I'm pretty sure there's no way out of this. It seems to me that if VAC really has been mistakenly detecting cheats, there's nothing Valve can do but keep very, very, very quiet and fix this as soon as possible, then kill all the programmers involved and torch their offices. Or maybe I'm missing an obvious solution. What do you think, readers?