links for 2009-11-10

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  Your Social Network is Limited to 150 Businesscard2.com Weblog
  No, it’s not. Another person builds on a mistaken understanding of Dunbar’s Number.
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  BookBlog Blog Archive In praise of semipermeable social boundaries - Adina Levin’s weblog. For conversation about books I’ve been reading, social software, and other stuff too.
  Adina does it again: “The Facebook model is biased against getting to know new people. The Twitter model is biased in favor of getting to know new people – slowly and gradually.”