Propelled by a significant increase in video viewing on YouTube, US internet users watched 16.8 billion online videos during April 2009, a 16% increase vs. March, according to monthly data from the comScore Video Metrix service.

Total viewing time amounted to 6.4 hours per viewer for the month, writes MarketingCharts.

Google Sites: Top Video Property

In April, Google Sites once again ranked the top US video property, with 6.8 billion videos viewed (a 40.7% online video market share), a 15% increase over March. YouTube.com accounted for more than 99% of all videos viewed at Google Sites.

Fox Interactive Media ranked second with 513 million videos (3.1%), followed by Hulu with 397 million (2.4%) and Yahoo! Sites with 355 million (2.1%).

Susan Boyle Video Boosts Viewing

Nearly 152 million US internet users watched an average of 111 videos per viewer in April. Google Sites, including YouTube, reached an all-time high of 107.9 million video viewers during the month. Fox Interactive Media ranked second with 58.8 million viewers, followed by Yahoo Sites (45.4 million) and Hulu (40.1 million).

Videos of Britain's Got Talent contestant Susan Boyle, posted in mid-April, may be partly responsible for the surge in YouTube viewing. Mashable reported that the video of Boyle's performance in the show's semi-finals was among the most viral in history and was viewed nearly 50 million times during the month on YouTube and other sites.

Other online video findings from April 2009:

• 78.6% of the total US internet audience viewed online video.
• The average online video viewer watched 385 minutes of video, or 6.4 hours.
• 107.1 million viewers watched 6.8 billion videos on YouTube.com (63.5 videos per viewer).
• 49 million viewers watched 387 million videos on MySpace.com (7.9 videos per viewer).
• Hulu accounted for 2.4 percent of videos viewed, but 4.2% of all minutes spent watching online video.
• The duration of the average online video was 3.5 minutes.