Chris Smith, Director of Optimization Strategies at KeyRelevance, references the growth impact of image on search, both from commentary at this year's SES San Jose and from his own thoughts. Blended search is expected to be the next natural progression of search optimization as more video and media are incorporated into campaigns.
Chris commented that at this years SES, a Microsoft Bing representative "stated that after regular web search, Image Search was their next most-popular feature."
From Chris's blog:
"With the advent of “blended search” or “Universal Search”, where images and other vertical search content are mixed into the traditional keyword search results listings, the usage picture becomes a bit more blurred. Users are now able to find image content in the regular search results, and they don’t always have to click into the specific image search pages to be finding and clicking through to that content."
For more, you can check it out right here.