Well, I don't even think it matters because whether or not you pur a limit on it, people will say they are 13 after the first time it says "Sorry, you are not old enough to register." I've played games that had an age limit and did the exact same thing.
Well, they made a 13 year old restriction for three reasons. A, their could be language that their parents might not want them to here. B, usually kids under 13 are really stupid on the internet. They spam or they give away their location where they live which might lead to unpleasant things I don't want to talk about and C, we want to have more sophisticated group so they put that their to help prevent under-aged kids coming in. I was under-age when I joined but not anymore.
Any age would be fine if there was a PARENT CONSENT FORM that needed to be filled out. Why do it for a gaming website? because some kids want to play games on the internet and maybe chat too. they just have to be smart in some ways, and know not to use foul language or any inappropriate things in public areas. @ RaiderDawg, they prbobaly aren't spammers, don't just go blaming little kids.
TRUTH: I am actually 11, but 12 in less than a month.
oh, i should of made this more clear at the start, post what you think of under 13s and if you are under 13 say somthing. if you are over, just give your opinion and advice.