Via SmartMobs (I think)

Joi Ito provides a lengthy description of the evolution of leadership, community and cooperation in on-line gaming. Far from being an idle pasttime, large scale games like World of Warcraft require a significant time commitment on the parts of the players.

...the larger raids are scheduled in advance with people preparing and showing up at the scheduled time, many smaller raids are organized at the spur of the moment where a leader is designated on an ad hoc basis. To be successful, a raid requires particular class compositions sometimes requiring our guild members to reach out to people they don't know to join the raid. We are getting better at raiding and many of these "pickup" members end up joining our guild eventually.