• by Gavin O'Malley  @mp_gavin, September 19, 2012

It wasn’t long ago that Google had virtually no display ad business. Remarkably, the historically search-focused company is now expected to earn more U.S. display ad revenues than any other company this year.
 
The new prediction, from eMarketer, puts Google’s share of the display ad market at 15% by year’s end. If accurate, Google is poised to command more share than any other company in each of the U.S. search, display and mobile advertising markets.
 
All told, Google is expected to take in $2.3 billion in U.S. display ad revenues, this year -- up 38% from nearly $1.7 billion in 2011, according to eMarketer.
 
Facebook, meanwhile, is on pace to earn about $2.2 billion in U.S. display ad revenues in 2012 -- up 24% from $1.7 billion last year. Yahoo -- the longtime leader before Facebook topped it last year -- will see its share fall further.
 
Overall, the U.S. display ad market will grow 21% to $15 billion from $12 billion in 2011, eMarketer forecasts.
 
The research firm attributes the continued growth of both Google and Facebook as advertising platforms, along with the continued health of banner spending. That trend, in turn, has been largely due to an expansion of inventory, aided by mobile growth and increased spending growth on digital video advertising -- YouTube in particular.
 
As eMarketer notes, its overall forecast for display has been slightly reduced from the previous one to reflect the mix of lower prices for display advertising on ad networks, combined with the reluctance of some major brands to make extra-large investments in digital display advertising.
 
Regarding Google’s success, eMarketer cites several factors underpinning the company’s ascent to market leader, including the continued strength of its ad network, video advertising on YouTube and mobile display advertising on AdMob.
 
Yet the company's newfound lead also comes as Facebook ad revenues have fallen short of expectations set in February, when eMarketer predicted that U.S. display revenues at Google would trail Facebook just slightly this year. eMarketer cut its ad forecast for Facebook earlier this month.