engine - 5:59 pm on Jan 18, 2008 (gmt 0)

comScore , a leader in measuring the digital world, today released its comScore Video Metrix report for November 2007, indicating that more than 75 percent of U.S. Internet users watched a video online (including both streaming video and progressive downloads), averaging 3.25 hours of video per person during the month. Google Sites, which includes YouTube.com, increased its video market share by more than two percentage points to 31.3 percent from October to November.

comScore Online Video Market Shares November 2007 [money.cnn.com]

Those are pretty big numbers.