That’s 50 percent of all Americans, not just those who say they are online. Six years ago, when Pew first conducted a similar survey, only 5 percent of all adults said they used social sites, like Facebook, LinkedIn or MySpace. It is a sign of how deeply and widely social networking companies have penetrated the lives of ordinary people and in turn, transformed the ways in which people communicate, authorities govern and companies sell things. Parents use Facebook to vet nannies, car makers to launch new models, police to keep tabs on suspects. Federal government authorities are preparing this weekend to use social networking sites for hurricane preparation on the East Coast. The Pew survey found that among adults who are online the rates of participation are higher: 65 percent, according to the survey, up slightly from 61 percent last year. Get the full story at The New York Times