Eh... Censorship in games is rampant, a7 (you mind if I call you that?). Sure, there are games that try to have mature content, but look at Postal 2 and the reaction, it's banned in MANY countries, look at Mass effect and the response it got because of one scene.
It might be the developers and publishers themselves that censor the games, but make no mistake, games are very much censored, far more than they should be. With a movie you can get away with being daring, even if you have to change something because it's too much, it's not that big a deal. It's easy to do, it doesn't cost much. With many games you don't have that option, either it's a game that has a meaning, with a story, far, far longer than the story of the regular movie, where every scene is needed. A lot of the game would have to be remade in that case. The other possibility is that whatever's censored out is the main attraction of the game, as in the case of Manhunt or Postal, or whatever.
Writing a mature story for a game, with this always in mind, is hard. To make a compelling story, that truly shows that violence is violent, and bad, you have to have a violent game, but whatever your intentions are, you will be accused of glorifying violence in your game, and you will get a stricter rating than a movie would. You have to compromise. Sexual content is even worse. Both, and you're just begging to have your game outlawed.
Despite the threadmakers... Crudeness, I can't help but disagree with the judgement, if not the reasons behind it. The argument that a game is just a game and doesn't teach you how to be a violent killer is flawed. Several militaries use video games, or similar simulations, to desentize their troops from violence, to teach combat situations.
However a game, like any other medium, movies, books, music, even though it may be interactive, can and should be a work of, if not art, then at least something akin to it. A game should be able to take up the same subjects, and treat them the same way, for whatever reasons. There are horribly violent movies with meaning, American history X, documentaries, whatever. But there are also horribly violeny, even more violent movies that lack a meaning. That is JUST for entertainment purposes. The same should be true for video games. While some of us may not agree that it's good entertainment, it should be avaviable for those who do.