Betakit has a good overview of the new neighborhood social networks here.  These businesses are hard to scale and require users to be open to their neighbors…not always a welcome thing.  The upside, however, is huge.  Just as facebook encouraged people to share more about themselves, the winner in this segment will figure out a way for neighbors to do the same. The early leader seems to be NextDoor, with $18.6 million from Greylock and Benchmark Capital
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