• by Mark Walsh  @markfwal, June 15, 2011

Mobile video always seems to call for the same characterization: small but fast growing. According to Nielsen's latest cross-platform (formerly "Third Screen") report released today, the mobile video audience in the first quarter reached 28.5 million, up 41% from a year ago, and about 20% from the prior quarter.

That's not too shabby, but that's still only about 10% of the 231 million Americans aged 13 and over that use a mobile phone. And it's been hovering at that level for the last couple of years. There haven't been big spikes in viewing, despite the growing proliferation of smartphones -- now estimated to have reached 35% penetration among U.S. mobile users, according to Nielsen, which has projected it will surpass 50% by year's end.

Obviously, mobile video hasn't kept pace with smartphone expansion. The Nielsen figures don't include tablets, which offer a more promising platform for mobile video because of their larger screen size. To date, many of the cable TV, as well as Netflix, ventures in mobile video have been focused on iPad apps. Perhaps at some point mobile video will be synonymous with tablets.

Where the gap between video on mobile phones and in traditional media really becomes clear is in time spent. TV remains dominant in this regard, at an average of 158 hours, 47 minutes a month. By contrast, mobile video viewing averages only 4:20 hours per month. That's actually not that much different than on the desktop Web (4:33 hours). Time spent watching mobile video is up 20% from a year ago, while it's up 34.5% online. The Web audience, of course, is also far larger: 142.5 million to mobile video's 28.5 million.

Teens and African-Americans are the two most avid groups when it comes to mobile video consumption, watching 8:40 hours and 6:30 hours on average a month. Blacks, as well as Hispanics and Asians, also own smartphones at higher rates than whites. In terms of gender, mobile video viewership tends to break evenly, with men and women aged 18 to 49 watching 4:20 hours a month.

As more and more people add tablets to their array of devices, it would make sense for Nielsen to add tablets as a separate media category in its cross-platform report along with TV, DVR-viewing, the Internet and mobile. That would give a better idea of the size and composition of the nascent tablet video audience.