Facebook Leads Yahoo, Microsoft in Display Ad Market with 176B Impressions

"We see this trend as a reflection of the growing comfort and appetite from brand advertisers who are willing to experiment with social inventory," Squali said in a May 13 research note. "With improving targeting and conversion, this inventory could overtime eat materially into the expected growth of premium display revenues."

Moreover, he said Facebook will continue taking share from portals as users spend more time on the social network. Over time, advertisers will move from banner ads that are sold at a remnant price to more interactive ads that are sold at premium prices on Facebook, MySpace and other social sites.

Fox Interactive Media and AOL rounded out the top 4 and 5 display ad spots, with 4.9 percent and 2.9 percent market shares, respectively. Google, the undisputed leader in keyword-based search advertising has struggle to find momentum in display ads, took 2.4 percent share for the sixth spot on the list.

Some analysts want to put Google's video ads from YouTube into the mix, and Google would undoubtedly rate higher than it does. However, comScore said it measures display ads as static and rich media ads and excludes video ads, house ads and "very small ads."

More generally, comScore said U.S. Internet users saw 1.1 trillion display ads during the first quarter, a 15 percent increase from a year ago and a record. Advertisers spent $2.7 billion for Q1 in the U.S., with the average CPM coming in at $2.48.

All of this is to say, the economy is recovering after the recession crippled the industry in 2008 and deep into 2009. "This pickup in activity should bode well for the online advertising industry as we move forward in 2010," said Jeff Hackett, comScore senior vice president.

Who was doing all of the advertising?

Telco carriers took 3 of the top 5 display ad positions, no doubt touting new smartphones and various data plans. AT&T led the way with 26.3 million impressions, followed by Verizon with 21.8 million views. Sprint captured the No. 5 spot with 10.1 million impressions served.