Facebook chartA release by ComScore revealed that Facebook accounts for nearly 1 in 3 ads in the U.S.

The total number of online ad impressions served in Q1 of 2011 was 1.1 trillion, of which Facebook alone accounted for 346 billion impressions. This puts Facebook on target to serve 1.38 trillion impressions for 2011. Facebook has almost doubled its market share from Q1 of 2010, which now stands at 31.2%. This is 3 times as much as Yahoo, 8 times as much as Microsoft and 12 times as much as Google.

AT&T was one of the highest online display advertiser for Q1 2011, accounting for 1.8%. Other top online display advertisers included Experian, Intuit, Groupon and Weight Watchers. ComScore also revealed 293 advertisers spent at least $1 million on display ads during the quarter.

It is not just about volume but also the quality of ads being improved explains Jeff Hackett, comScore executive vice president. “We are now seeing more than one trillion display ads delivered every single quarter and nearly 300 individual advertisers spending at least $1 million a quarter on display, numbers which underscore just how large and vibrant the online medium has become. And it’s not just about the volume but about the quality of the advertising experience that can be delivered as we see continued investment in compelling, high-quality creative that helps cultivate long-term brand equity.”