According to Web 2.0 evangelists, social networks bring people together. Twitter is about collaboration and communication, after all.
But I've been thinking that in the political arena, social media may actually hurt democracy because people can post all sorts of snarky comments because they never see the other people. I saw a lot of snarky comments on a Forbes blog about the Olympics & politics -- many were mean-spirited and were not in keeping with the tone of the original article.
The Economist recently ran an article that looks at the topic. Worth checking out: "The brave new world of e-hatred: Social networks and video-sharing sites don’t always bring people closer together."
For companies looking to do more with social media, what's important is to keep in mind that there are some dark alleys in the social media world, and that it's important to pay attention to what's being said, how it's being said before posting comments.