Social networks are enabling sociologists to study the way that a person’s social group affects their personal behavior/decisions, especially in things that can have public policy implications, like from smoking and obesity.

"What all these studies do is force us to start to kind of rethink our mental model of how we behave," said Duncan Watts, a Columbia University sociologist. "Public policy in general treats people as if they are sort of atomized individuals and puts policies in place to try to get them to stop smoking, eat right, start exercising or make better decisions about retirement, et cetera. What we see in this research is that we are missing a lot of what is happening if we think only that way."

More than almost any other internet-based phenomenon, social networks seem to simply mirror organic constructs that humans have already been maintaining in the real world for a long time. There’s been much talk of the ways that technology occasions reorganization in our lives (Blackberries, laptops, and universal phone numbers being prominent examples), but social networks are probably the biggest example of it working the other way. We created them to make sense of our natural, real-world ways.

It’s no secret that the reason people find them so exciting is the level to which they resonate with/mirror the societal constructs we already create in the real world – friendships, affinity groups, job-related organizations and contacts. It’s very cool to read that this holds up so well it can be studied, that the bounds of the virtual and the actual worlds overlap so much here that it’s possible to study things happening on social networks as being simply part of normal human behavior and not just human behavior as it occurs online.