Facebook was the dominant outlet for U.S. online display ads in the Q1 of 2011, far outpacing Yahoo, Microsoft and Google.
Facebook accounted for 346 billion impressions, from January through March, according to a new report from comScore. That was nearly one third of all display ads and double the number Facebook delivered a year.
Yahoo had about 111 million impressions, or 10% of the market during Q1. Microsoft sites, which include Bing and MSN, had about 54 million impressions, or 5% of the market.
comScore Ad Metrix data shows that nearly 1.11 trillion display ads were delivered to U.S. web sites during the quarter.
The latest raking underscores Microsoft's challenges as it tried to build more online advertising revenue.
Meanwhile, Jeff Hackett, comScore executive vice president, said nearly 300 individual advertisers spent at least $1 million last quarter on display, "numbers which underscore just how large and vibrant the online medium has become.
AT&T was the top online display advertiser in the first quarter with 19.5 billion impressions, or for 1.8% of display ads."