The thing about VAC is that it's archaic and easy to bypass. Even Punkbuster catches and disables more cheaters than VAC does.
Left 4 Dead has a massive community of Cheaters, and all of them are using the same two aimbot suites for several months to a year now.
Valve can't program worth half a crap. AI is garbage, Steam is sub-par, and VAC is ineffective at best.
No other developer has games where the friendly AI has a habit of wandering off on their own to get owned, healing at times where running is better, and healing when under fire.
No other developer has an Anti-Cheat suite so outdated that you can find an 8 month old MP cheating suite and it works with the current game flawlessly.
Oh, and Dark Night, those kids were disturbed long before they played CoD and watched porno.
Video Games are a scapegoat manufactured by the fascist right-wing parties of various governments from the U.S. and U.K. all the way to modern Germany and Australia. I've been playing the nastiest crap since 12 and I of course have no thoughts of senselessly dismembering, mutilating, killing, raping, etc. whereas some do. Why do they only affect the infamous but altogether minuscule sub-group when so many are unaffected?
Simply put, it's preexisting mental instability and/or bad parenting. The mentally and emotionally stable make up the vast but unrecognized majority, while the smallest minority in the gaming community gets all the attention for their transgressions despite the games never being a factor in said mental instability.
First it was books, and they were burned en masse. Then it was movies, and of course there were protests. Now it's video games, and then next I assume it'll be the next big entertainment medium to come about in the next century. Video games are no different from movies and books. The interactive nature doesn't negate the fact that movies and books continue to do more graphic and disturbing things in their stories.
Saw features brutal torture and snuff. No one cared about it due to it being a movie. Various books involve rape, gore, snuff, abuse, drugs, etc., but likewise, no one gives a rats ass about it. All of a sudden just because you follow a storyline while pressing a button and moving a stick, it's the ****ing antichrist, despite video games being extremely tame compared to the soft-core porn aspects of R Rated movies, the brutal and graphic death scenes in many movies, and of course the portrayals of genocide, racism, etc. in many movies even today.