Dunbar & World of Warcraft
In my initial blog entry on the Dunbar Number I presented some statistics on group sizes based on the online game Ultimata Online. In it you could clearly see the power-law (pareto) curve, with diminishing returns at around 150, with most groups being 60 in size:
More recently, Nick Yee and other researchers at the PlayOn Blog have been researching the behaviors of players in the popular World of Warcraft online game.