The Solitude of Social Media
One of the unique things about Twitter in 2006 and 2007, especially during the first tweetups was that it was a network of strangers who became friends without meeting in person. The people I became friends with in 2006-2007 are still friends now, to some degree. I met them every week at tuttle events and tweetups.
At the same time Facebook was a network of friends from university, which then became friends from work, to friends from various activities.