Google sites have topped the online video content property with 141.1 million unique viewers in the US, primarily driven by video viewing at YouTube, according to a comScore report.
Microsoft captured second position with 48.8 million viewers, followed by Yahoo! sites with 46.7 million viewers in February 2011.
VEVO and Viacom Digital secured fourth and fifth position, with 45.9 million and 45.2 million viewers, respectively.
According to the report, Google sites had the highest number of viewing sessions with nearly 1.8 billion, and average time spent per viewer at 262 minutes, or 4.4 hours.
Americans viewed 3.8 billion video ads in February, with Hulu generating the highest number of video ad impressions at more than 1.1 billion.
Tremor Media Video Network ranked second with 548.3 million ad views, followed by ADAP.TV (396 million) and SpotXchange Video Ad Network (343 million).
The report revealed that 82.5% of the US Internet audience viewed online video, and the duration of the average online content video was 5.1 minutes, while the average online video ad was 0.4 minutes.