According to a new mobile video report from The Nielsen Company, the number of U.S. mobile subscribers watching video on their mobile devices rose more than 40 percent year-over-year in both the third and fourth quarters of 2010, ending the year at nearly 25 million people. These mobile video users watched an average of four hours and 20 minutes of mobile video per month in both the third and fourth quarter of 2010–a 33 percent and 20 percent year-over-year increase in each quarter respectively.

The growing popularity of mobile video is due, in part, to the rapid adoption of media-friendly mobile devices, including smartphones. Whereas in Q4 2009 only 23 percent of US mobile subscribers had smartphones, by the end of 2010 smartphone penetration had reached 31 percent. Over time, it also has become easier to find, view and share mobile video, either via mobile apps or the mobile web.

Learn more: Download State of the Media - Mobile Usage Trends: Q3 and Q4 2010.