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Facebook in July became the number three site for watching online video in the United States, a web metrics firm says. The world's largest social network jumped from number four in June to take third place last month with 46.6 million unique video viewers, ComScore said in its monthly report released Monday. Facebook had 43.3 million views in June.

Google, driven mostly by video viewing on YouTube, remained the top site for watching online video, followed by Yahoo. Google had 143.2 million unique viewers in the month, while Yahoo had 55.1 million.

VEVO, meanwhile, fell from number three in June to number five in July with 43.9 million unique viewers, while Microsoft rose to number four with 45.5 million viewers. Microsoft was number six in June.

However, the rankings were much different when based on the amount of time people spent watching videos on the sites. Google led the pack with 282.7 minutes, or 4.7 hours, per viewer, but Hulu, which was number 10 in unique viewers, was second in minutes per viewer with 158. Hulu, which offers TV shows and is owned by NBC Universal, News Corp. and The Walt Disney Co., was the only other site to have triple-digit viewer minutes.

With the exception of Disney online, Facebook users spent the least amount of time watching video in July at 18.3 minutes each on average. VEVO was third behind Google and Hulu at 68.5 minutes.

Overall, 178 million U.S. Internet users watched online video in July, compared to 177 million in June, ComScore reported. Users watched an average of 882 minutes, or 14.7 hours, each, slightly more than the 870 minutes in June.

In looking at video ads, ComScore found that Americans watched nearly 3.6 billion in July, with Hulu generating the highest number of video ad impressions at 783 million. Hulu ads reached 27.9% of the U.S. population in July, while video ads as a whole reached 44.5% of the population.

Hulu in June launched a paid subscription service that would also be supported by advertising. Hulu Plus, which is available by invitation only, makes it possible for users to access their favorite sitcoms, dramas and more over many devices beyond a Mac and Windows PC.

FURTHER READING:

-- TwitVid Launches Video Ad Network

-- Hulu Launches Premium Video Subscription Service

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