The number of unique visitors viewing video on Facebook totaled 45 million in March 2012, an 8 percent decline compared to March 2011, according to comScore's U.S. online video rankings.
Google sites, which include YouTube, drew the highest number of unique viewers of all websites: 146.1 million in March 2012, an increase of 2.9 million compared to the same time last year.
Overall, the average viewer watched 21.7 hours of online video content in March 2012, according to comScore. On Google sites, people watched an average of 7.1 hours and on Hulu, 4.6 hours - the highest among the top 10 video content properties.
