Recently a report from eMarketer estimated US mobile ad spending by format through 2015. I made the following graph to illustrate their estimates in the report.
Good news, mobile messaging takes the largest piece of the mobile ad spending pie, accounting for $327.3 million in spending in 2010 and $442.6 million in 2011. Bad news, mobile message spending is overtaken by both mobile search and banners in 2012 as smartphones gain market penetration.
Looking on the bright side though, mobile message spending is estimated to continue its growth year over year, and still maintains a considerable lead over mobile video spending. Also, spending on mobile ads as a whole is estimated by 2015 to be $4.4 billion!