This is an interesting piece of sociological research by danah boyd, that foreshadows changes in the way that sociology research will be conducted in the future.
What is the paradigm shift? Social networking sites force people to reify their social relations - they put all of that data into one accessible, easy-to-mine place.
The other important issue that danah's paper raises is that despite the denial and rhetoric to the contrary, the United States has one of the most pervasive and manifested socio-economic class divisions in the modern world.
I regularly keep going back to the thought of using network analysis to reveal the real power structure of governments - which business leaders met which government leaders for what reason when?
This issue has become more critical with the rise of special interest groups and lobbies. After all, network analysis is already being successfuly used by governments to track the activities of their enemies.
There is a fascinating interview with Valdis Krebs of orgnet.com about mining publicly available information on the 9/11 hijackers using network analysis. Why not use these tools for the real benefit of civil society?
The more paranoid will point out the connection between Accel Partners, the venture capital firm that initially invested in Facebook, and the CIA.