MySpace.com received 72.73 percent of the market share of U.S. visits in May 2008 among a custom category of 58 of the leading social networking websites according to Hitwise. The market share of U.S. visits to the social networking custom category decreased 1 percent in May 2008 compared to April 2008 and has decreased 6 percent year-over-year.

Among the top 10 social networking websites, Facebook ranked second by the market share of U.S. visits with 16.24 percent, followed by MyYearbook, which received 1.40 percent. MyYearbook experienced the largest gain in market share in May 2008 among the top five visited websites, increasing 384 percent compared to May 2007. Facebook and BlackPlanet followed, increasing 42 and 9 percent, respectively.

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