eMarketer expects Yahoo!’s share of net US display ad revenues to decline again this year to 7.7%, down from 9% in 2012 and 11% in 2011. In 2008, Yahoo! accounted for 18.4% of all US display ad revenues. By comparison, Google and Facebook will see their shares of display ad revenue grow to 17.6% and 15.5%, respectively, this year. Read the rest at eMarketer.