In summary, 45% of of web users are reached through these sites. Good summary of some relevant sites, but I wouldn’t call them all “social networking” sites. What isn’t social on the web? They’re a mix of sites that try to encourage socialising, sites that facilitate self-publication, sites that facilitate finding each other, sites that facilitate grouping according to interests…a big mix which I think is silly to bunch together. I guess the list is more for advertisers to reach consumers, it is about sites that have the greatest reach, sites that people gravitate too. Anyway, quick stat and quick rant over.