Google's YouTube accounted for 75.43 percent of all US visits among a custom category of 63 online video websites, followed by MySpaceTV with 9.01 percent and Google Video with 3.73 percent, according to May 2008 Hitwise data. YouTube's traffic was up 26 percent from the year-earlier period, MarketingCharts writes.

The Online Video category accounted for 1.14 percent of all US internet visits in May 2008 - a decline of 9 percent compared with May 2007. Despite the decrease in US visits, however, the amount of time spent on the websites increased 6 percent for the week ended May 31.

"YouTube continues to be the main destination for consumers to find and view online videos," said Heather Dougherty, director of research, Hitwise. "The majority of searches driving traffic to the website are for the YouTube brand, highlighting [its] prominence and strong brand awareness in the video arena."

New and Returning Visitors

In May 2008, YouTube received 82 percent of its visits from returning visitors (from within the previous 30 days).

Among the top five online video websites by market share, MySpaceTV and Google Video followed with 64 percent and 54 percent, respectively.