Friendship helps people write community into being in social network sites. Through these imagined egocentric communities, participants are able to express who they are and locate themselves culturally.

A perceptive and detailed analysis of the Dunbar Number - and why some of the hype around it is misguided.

"the strength of social contact between people cannot be measured by frequency or intensity; a better measure is the number of communication channels used by people" - I like Chris' ideas, but need to think a bit harder on them.