Here's something from Jyvaskyla (your site can't handle umlauts), Finland, the heart of the online gaming community. You, know, because of all the vikings and trolls and werewolves (hell, I know nothing about Finland, except that Conan O'Brien is the President).
Online multiplayer games enable the formation of lasting relationships
Online multiplayer games typically encourage interaction between players: some go even as far as demanding it. Collaboration with other players may be a prerequisite for making progress in a game, or a game may be based on competition between players.
Yeah. Social interaction is a requirement of the action--- you can move though lesser gameplay as a loner, but to experience the full depth of the environment, you need to team up.
I remember playing the MQMPAG (multi-quarter multi-player arcade game, or "mac-kyoo-empag"; see, anyone can make up this crap) Gauntlet, and I would jump into a game with three complete strangers and play until my quarters ran out and then someone else would take my place. And not once did I ever form a bond or expand my social network with anyone.
Go to any pool hall or bar with arcade games or pool tables and see how many people play a game with a stranger just to test his skills. No bond is formed, but maybe a beer is won.
So now, the social interaction is written into the online game. The designer, that nerd in his mother's basement, wrote in the interaction so that someone would play with him. Yeah, you heard me, nerd.
No, my needs for a social network are fulfilled by The Grassy Knoll Knitters. Me and the girls sit around and sip our cups of Darjeeling (with a splash of Boodles for inspiration) and knit beanies for the emo and sk8ter grrls in the hood. Oh, until Shirley gets up on her high-and-hard and goes on to claim that a third man was behind that fence in Dealey Plaza, a 7-foot albino wearing a Clara Bow wig, and Laverne just can't take it and jams that knitting needle into Shirley's right butt-cheek. Oh, those are heady times. Heady times, indeed.