New product announcements and service demos at CES confirmed what many pundits predicted, a variety of mobile devices -- media tablets and smartphones, in particular -- and digital media streamed from the cloud was a pervasive theme.

Indeed, the future upside opportunities for mobile content look very promising.

According to the latest market study by eMarketer, ad-supported mobile content revenues will exceed $1 billion by 2015 -- with the fastest growth coming from advertising support for mobile video.

Last year, U.S. mobile video revenues from advertising reached just $37.5 million, but by 2015 advertisers will spend $213.6 million on ad placements that support mobile video content.

Regardless, that's still lower than the amounts spent on advertising against mobile games and mobile music -- estimated at $65.3 million and $181.4 million, respectively in 2011. Both are forecast to grow to $269.1 million and $591.5 million, respectively, by 2015.

Looking forward, eMarketer now estimates that 29.9 percent of all mobile content revenues -- or $1.07 billion in 2015 -- will come from advertising.

To date, mobile music has the greatest share of spend coming from ads, and it will hold that position, with advertising and promotion spend making up 73.9 percent of the total in 2011 and 79.3 percent by 2015.

The fast growth of mobile video advertising revenues will mean changes in the revenue mix. While ad dollars comprised just 5.4 percent of mobile video revenues in 2011, by 2015 it will more than triple to 16.5 percent.

By contrast, mobile gaming ad revenues will also rise as a proportion of the total spend, from 13.8 percent in 2011 to 17.4 percent by 2015.

The eMarketer forecast of mobile content spending starts with a meta-analysis of data from dozens of research sources -- as well as overall market trends and consumer behaviors around mobile gaming, music and video.