hp labs on twitter
The HP Labs report on Twitter is worth reading in full...and not just for backing into an active user number. I found this graf particularly noteworthy: "These initial observations suggest a systematic investigation into the nature of the social networks that actually matter to people. By networks that matter we mean those networks that are made out of the pattern of interactions that people have with their friends or acquaintances, rather than constructed from a list of all the contacts they may decide to declare." Here's to more systematic investigations.