Jamusta, I'd say the vast vast majority of online gamers are in their teens to 20's. AH is sort of a niche community, the average age of the players here is probably 2-3 times the average age of most games.
Probably 99.5% of them are white or asian.
Everyone else.. J00 Sux0r!!!11!1. I r t3h 1337 R0x0r.111!!!one.
And gimme a friggin break, btw.
Just because I'm a ****up doesn't mean I don't know how to spell. I use 1337-5p34k because it is funny as hell. I also use it it ridicule people, not that they understand it half the time.
I think most people on the internet are smarter than your average person, although how that translates into "success" isn't clear. I think it actually is inversely related... the more time you spend on the internet, the less likely you are to be any sort of success in life. Or perhaps it is a direct correllation. The more you suck at life, the more time you spend on the internet.
Anyway, I wouldn't say "leetspeak" is the end of the world as we know it... mostly just kids/young adults having fun by being stupid.