Idiotic parents, religious zealots, the general riffraff that think games are evil. There's the reason that there's so many ridiculous restrictions, those idiots are allowed to vote, and won't let anyone with a modicum of sense into a position of political power.

Not everyone has it together -- the assumption is someone like that will play a game or a bunch of games like this and then go kill someone.
But it's backwards.
Real-life violence produces violent games..generally it doesn't work the other way around.

Here the ratings have the force of law, presumably D2D are doing it to say they fully support the rating system.
This is probably the exact reason D2D do this, to say "Hey we've done our part" when wankers like that complain to them about how they're destroying society
Yeah noones ever answered the challenge of why alcohol is sold given how often IT (or people using it) causes problems

Personally, I'm starting to believe in keeping violence-glorifying media (not just games) out of people's hands until they've proven the ability to process it. For the most part, that ability comes with age, and since most parents don't pay close enough attention to know whether or not their child has developed that ability, an arbitrary age requirement is arguably the most effective approach.
While I started playing hyper-violent games at a young age (so did most people I know, and presumably most people on this site did too), and have turned out as one of the most unwaveringly pacifistic people you'll ever meet, I have met too many people for whom it seems that the violence-worship has stunted their growth, particularly in the areas of empathy and compassion. This is of course not a scientific observation, as there are always going to be lots of factors that influence the way somebody develops, but even with my skeptical approach to pinning blame, the consuming of violent media prior to achieving adequate maturity is a surprisingly common factor.
I probably sound like a heathen, since I know we gamers are supposed to defend our hobby to the ends of the earth, but spending time with families who have specifically avoided violence-as-entertainment in their children's upbringing has made me think on this subject a lot. They've turned out, for lack of a better term, well, whereas those who have grown up in households where violence-glorification has been allowed uncritically, have turned out... less well. And, sometimes, badly.
Again, not scientific.
Anyway, the reason for age restrictions was never as stupidly simple as "they will copy what they see." That's a straw-man argument that's been perpetuated for far too long. It's silly.
(Also, instantly labelling people as zealots and fanatics is a very zealous and fanatical thing to do.)

At the risk of sounding scientific, what other diffrerences are there between the sample families?
I've been arguing for an 18+ certification here ever since GTA3 was refused classification because it had the option which was 100% up to the player and never presented as part of a mission to kill hookers that you've had sex with (apparently they don't care if you kill hookers who you haven't fucked). Our ratings have the force of law (because unlike the ESRB, the OFLC is government run) and that seems to work pretty well, if anything having the maximum rating being 15+ lets younger people get games that the hysterical harpies bitch about. Personally I'd have rated several games I own as 18+, Gears Of War 1 & 2 and GTA4 most notably but we don't have an 18+ and now "children" (IE: Anyone 1 day or more below the magic maturity age of 18) can get them
I couldn't give a toss about their alleged effects, I want consistency in ratings. If Gears or GTA were movies, they'd be rated R, so should the games be.

Yes, exactly - there was an entire paragraph that I deleted, and you've managed to cover it with one sentence.
It's totally plausible that if parents just let their kid play whatever they like, without giving a shit, then the games are going to have less of an influence on the kid's development than the fact that the kid has parents who don't give a shit. And it works the other way too; if a kid's raised by parents who care enough to regulate what they play, they're going to benefit from having parents who care (and if a kid has parents who are complete dicks about controlling what they play, then they will suffer the effect of having parents who are complete dicks).
Also, I'd say the fact that my Mum really didn't like me playing Wolf3D and Mortal Kombat had a far more positive effect than if I'd been prevented from playing them, or even if I'd just never played them. I knew she didn't like the games, I knew what she didn't like about them, so these two facts were in my mind whenever I played them. They were part of how I processed what was going on in the game. And I'd like to think that age restrictions have a similar effect on kids, even when they're ignored, but it's not likely since the restriction labels are usually so crass.
(I'm now forcing myself not to go into a lengthy rant about the way so few parents (and adults in general) treat children as people, since it's only slightly relevant - it's enough to say that I wish restrictions like this, whether enforced by law or by parents, were actually explained)
Anyway, yes, my belief on this subject is not set in stone, and I would be happily swayed one way or the other by hard facts or even sensible arguments. But both of these are almost completely absent in this debate - on both sides.

Unfortunately the OFLC is not consistent at all, and some games can pass as 15+ while others with the same or milder content are banned. They just refused classification of Risen (the new RPG by Piranha Bytes) because some quests reward the player with drugs and/or sexual favours; The Witcher made a much bigger deal out of sexual rewards (even including collectible cards for women Geralt has scored with!) but it was allowed with a rating of MA15+.

Yeah, the OFLC thing is indefensibly absurd. I can't believe it hasn't been fixed yet. Why hasn't it? I can't think of a single argument in its favour.

The only way to get hard scientific data on the subject is with a city of twenty thousand or so test families that are controlled under laboratory conditions so you can do a comprehensive analysis of a realistic population that will lead to a genuine theory on the causal natures of youth violence.
Number 1 amongst those causes might end up being "locked in a lab and controlled like a test subject"
I defiinitely agree that parental care matters. A susceptible kid will probably turn psycho if his parents abuse the shit out of him even if the only game he's got to play is nintendogs. Likewise one who isn't susceptible probably won't turn psycho even if he's raised from birth on Gears of War
In Fallout 3, Med-X used to be Morphene, now because they basically forced the change I'm not tempted to shoot up on real drugs before a fight, just fake ones. Thanks OFLC!
Its in desperate need of a rebuild, frankly its running a band aid solution to something it was never designed to deal with.

Not the merchants fault, it is whomever independent/government organisation that enforces it. Also, as a minor/juvenile the rules are different. While individuals may be okay, you can't say that for all. Adults we expect to behave differently (and think first for themselves), but it's not always the case.
Australia badly needs a R18+ rating. Like Aliasalpha, I also argue for a bit more consistency in this country.

This.
While I am not a censorship person in the least, quite the opposite really, it is rather naive to think media does not effect us in all kinds of ways. As a sociology major I have studied it over and over again, and it's quite easy to see it in everyday life if you look hard enough... look at what Miami Vice did to men in the 80's, lol.
While I firmly believe people have the ability to shut off this influence before it causes them to behave violently, unless they already have mental issues, with kids it is not so simple. Kids are not as developed mentally, and are much easier to manipulate through media. For this reason, violent games and such can be more harmful to them than to adults.
That said, I think it is the parents responsibility, not goverment or GOG, to prevent them from playing those games. With GOG it is a simple as restricting the child's computer or Internet access, or not allowing them to have a method of payment.

The ESRB is a private organisation and so they can't have any legal power in america (can you imagine private companies influencing american governmental policy? Pshaw!), D2D would either be doing this as a show of compliance to counter bitching or as a way to expand their business outside of america into places where the ratings are legally binding

Hicks again. :)

He wasn't wrong about much...