Bing has over 30% of searches in the US

"Experian® Hitwise®, a part of Experian Marketing Services, announced today that Google accounted for 64.42 percent of all U.S. searches conducted in the four weeks ending April 2, 2011. Bing-powered search comprised 30.01 percent of searches for the month, with Yahoo! Search and Bing receiving 15.69 percent and 14.32 percent, respectively. The remaining 69 search engines1 in the Hitwise Search Engine Analysis report accounted for 5.58 percent of U.S. searches."

Source:  Press Release from Experian Hitwise, 11th April 2011