U.S. teens spend as much time online - about 2.9 hours per day - as they do watching TV, writes MediaPost, citing a survey by CBSNews.com. Research for school was the most-cited online teen activity, with 90 percent saying they frequently or occasionally use the web for school work. Some 63 percent say they use email frequently or occasionally, compared with 53 percent who say they instant-message frequently or occasionally.

About 65 percent of teens say they have posted at least once on social-networking sites such as MySpace or Facebook, and 63 percent say they have read posts on such sites.

Some 59 percent say they frequently or occasionally download music, 44 percent report game-playing and 37 percent report watching videos online.