Nielsen reports that social networking in online communities and blogs has become a more popular Internet activity than e-mail. It is growing three times faster than the overall Internet and twice the rate of other top Web categories such as search, portals and PC software.

Nielsen estimates that one out of every 11 minutes of online activity on a global basis is attributable to social networks, blogging sites and other types of member communities. Moreover, these social-computing sites are being visited by more than 67 percent of the global online population -- a trend that shows no signs of slowing, according to John Burbank, CEO of Nielsen Online.

"Social networking has become a fundamental part of the global online experience" and "will continue to alter not just the global online landscape, but the consumer experience at large," Burbank said.

Expanding Demographics

Though social networking owed its initial popularity to support from younger Internet users, Nielsen notes that the audience is fast becoming much more diverse. Facebook, which Nielsen says is visited monthly by three out of every 10 people online, added 13.5 million visitors in the 50- 64-year-old age group last year, or twice the number that the world's No. 1 social-networking site had added in the under-18-year-old demographic in the same period.

Social networking is also becoming more mobile, with 19 percent of all U.S. mobile-device users saying they use their handsets for social-networking purposes -- up 156 percent from the year-earlier period. Nielsen also estimates that nearly three million U.S. mobile users were texting Facebook on a regular basis at the end of 2008.

Burbank also noted that an interesting connection is rapidly developing between social networking and live television, with 11 percent of the households that Nielsen sampled during this year's Academy Awards simultaneously following the...