During previous ComScore statistics Bing was breathing down Yahoo's neck in search engine competition within United States. Now, finally, Microsoft's search engine (Bing - a.k.a Bing Is Not Google) has become more popular than Yahoo. According to company's analytic data in December of 2011, Microsoft Bing received 2.75 billion search requests within United States while Yahoo received 2.65 billion search requests.
In result, according to ComScore, Bing owns 15.1% of American search engine market and Yahoo 14.5%. Even now Microsoft is still far away from Google which processed 12 billion search requests in month of December, 2011 and is currently leading with 65.9% of search engine market in U.S.
The remainder of search engine market is owned by Ask Network with 2.9% (531 million search requests) and AOL with 1.6% (287 million search requests).