'Flocking' behavior lands on social networking sites - USATODAY.com

John Tropea - Delicious Social Network

Those of us who study social networks believe they matter — that things do spread along social networks," says Claude Fischer, a sociology professor at the University of California-Berkeley. Whether theyre face-to-face or virtual, social networks influence human behavior and shape everything from finances to the way people vote, say Christakis and co-author James Fowler, a social scientist at the University of California-San Diego.