Americans spend most online time on Facebook

Computerworld - Ever wonder what your co-worker or friend is doing online? The Nielsen Co. has a pretty good idea what they're up to.

Nielsen Online reported this week that people spend more time on Facebook than any on other Web site. The study also noted that 87.25 million U.S. users visited Facebook from home and work during June, and each of those people spent an average of 4 hours, 39 minutes and 33 seconds on the site during the month.

Next in popularity was Yahoo and the sites and applications under its umbrella. More than 134 million U.S. users visited at least one of the Yahoo-owned sites or launched a Yahoo application during June, and they spent an average of 3 hours, 15 minutes and 55 seconds there.

AOL came in third, with users averaging 2 hours, 43 minutes and 10 seconds there. Google came in fourth, with 2 hours, 31 minutes and 8 seconds, while Microsoft came in fifth, with 2 hours, 12 minutes and 20 seconds, according to Nielsen.

Facebook has been on quite a roll.

Early last month, Nielsen reported that Facebook saw a 700% increase from April 2008 to April 2009 in the amount of time users were spending on the site.

Nielsen noted that Facebook isn't alone in its rapid rise. Twitter, though only the fifth most popular social networking site, saw users increase their time there by 3,712% over the same period.

The driver of Facebook's dramatic growth has been users who are far older than the college-age crowd that founded and built the site, according to a report issued last week by iStrategyLabs.

Echoing past reports about Facebook, iStrategyLabs data showed that while the number of Facebook's U.S. college and high-school-age users declined over the past six months, its popularity among the 55-and-older crowd is booming. In fact, the number of 55-and-older Facebook users showed staggering growth -- 513.7% -- in the past six months, the digital consulting firm said.

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