what I love about these threads is the people who come on and say "adults also play these games and they are fine". IME, the adults I know who play these games are socially maladjusted misfits.
For example: former flatmate G who spent most Saturday nights in his room getting drunk (on his own) and playing COD until 4/5 am (and intermittently swearing at the tv). In his mid-late 30s, didn't have a GF for years until he started meeting girls (from Russia and Ukraine) on t'internet. Had severe anger-management problems.
Or, friend's two flatmates - both in early 40s, one unemployed for about ten years (the other one paid his rent). Barely ever left the flat, developed weird obsession with friend's cat and tried kidnapping it went friend left it to go on a trip. Both have drug problems.
Or, friend's BF (can't stand the guy) - also has problems with drugs and alcohol, is employed (well done him), but also may have beaten up my friend on occassion (how wrong it is that these two are together can't even begin to be explained, but she refuses to leave him 
)
Or, DP's friend who is affectionately known as "unemployed guy". 30 y/o, longest he's ever held down a job for is about 3 months (which is his latest job - delivery truck driver for catering company). Failed his Bacc. about three times, despite being quite clever, spends most of his day either watching sports, or playing video games.
Ex's flatmate - in his 30s, barely left the flat, would spend all day playing WOW. Ex was his only friend.
Ex's second flatmate - severely depressed. Spent all day playing online, barely ever left the flat.
Maybe I just know all the extreme examples of gamers, but my experience is that the people who do routinely play these games have major problems with socialising with other people, rather mysoginistic/bizarre attitudes to women and problems with substance abuse. Really makes me want to run out and buy these games (in opposite world).