It depends on how one interprets a game really. For example, you could play through Call Of Duty 4 and think about how it depicts the horrors of war and such, or you could think about how it was nutty shooty fun woohoo. And sure, thinking about the horrors of war has a negative effect, but only on the mood, and you do learn something. Damn, look at me talking about a game i've never played. Anywho, I really don't think that first person shooters and other violent games have driven anyone with a normal brain to going on a shooting rampage. If that was true, there would be a hell of alot more cases of video game motivated shooting rampages. The unfortunate counter to this argument is that a murder or robber was once within 50 miles of an xbox, and therefore received its mind control signal or whatever and thus began his life of crime.
As for censorship, that's also bullshit. What do adults think will happen to kids if they see a tit or hear an uncensored swear word? Go on a one month crime spree? Does his brain automatically become damaged or something? And I don't think readiness to make big life choices should be determined by age, but rather by how a person acts. Okay, that's a bit harder to verify, but at least it's better than thinking that turning 18 magically makes you responsible and level headed. I don't think obscene material will hold any power over anyone if they'd simply stop taking it as a personal offense. That's what's really going on. People get offended by violence and sex in any form of media, therefore they want it banned. The trouble is that they can't just say that or they'll be laughed out of court, so they've latched onto the tissue thin "We're protecting the children!" excuse. The only problem with that excuse is that every child learns every swear word by the time they reach 5th grade, so censoring the words won't do any good, plus the children will then start swearing themselves just to see how much they'll piss of the adults. Children will always be rebellious, and you can't blame that all on games. Hey, why don't parents just stop using their bullshit excuses and just admit that they suck at parenting? Because that would soil their image as an angel parent sent down from heaven to foster the next messiah, who sneaks dads' playboys from behind his back. I still have to deal with this crap at 17. Not with my parents, they know I can handle mature content. However, Microsoft fished my age out of my hotmail account when I made my live profile and so now I can't download any M rated games or demos, even though I am 17 and 17+ is what it says on the box, not 18+. So it even effects me even when my parents don't restrict me from mature content. So yeah, censorship can go fuck itself.