The gap in spending between online search and online display is closing, and quickly, according to this June, 2011 forecast by online marketing firm eMarketer.

While search captured the early sweepstakes as the category offering the best ROI, that out-of-the-gate lead is narrowing. The prediction now is that sometime in mid-2014 the advantage will shift to display as the favored category, coupled with analysis that shows overall growth slowing from a 2011 high of 20.2% ($31.3B) to a 2015 assumption of 8.8% ($49.5B), nearly doubling today’s spending.

Technology, opportunity, metrics and platforms are all reasons for this growth. The opportunities presented by mobile coupled with the emergence of HTML5 and a host of other visual solutions likely account for the change in velocity.