Socializr Isolatr Snubster Networkr Backlashr
Michael Arrington thinks there might be a little (a little?) backlash against social networks, and mentions Isolatr and Snubster.
But he overlooks Nemester:
Nemester
The new way to make enemies™Nemester is an online community that connects paranoids, egotists, villains, and monomaniacs through networks of competing agendas and incompatable ideologies for bitter conflicts, mutual loathing, or to find their one, true nemesis.
And the backlash thing? It was hard work, but I dropped out of the social networks last year: see Unlinking From Social Networks, parts 1-8. They don’t make it easy, but you can in fact get redlined at LinkedIn, so you will never ever receive another invitation to join, if you don’t want to.