Google knocks off Yahoo as US display ad leader

Yahoo, the perennial leader in US display advertising, has lost its number-one spot in that market segment to arch-rival Google, according to an IDC report.

In this year's first quarter, Google's share of the U.S. display ad market rose to 14.7 percent from 13.3 percent in 2010's fourth quarter, while Yahoo's share shrunk to 12.3 percent from 13.6 percent. The news has to be encouraging for Google, which for many years was a minor player in display advertising. However, it has made big investments to improve its position, including spending billions to acquire DoubleClick and YouTube.