Google is still dominating the search engine market but Bing is gaining ground.
Looking at the global search engine market in January 2011, Google took home almost 68 % of all online searches but that marked a 2 % point decrease from December 2010. The number of searches run at Bing.com and Bing-powered sites collectively rose by 6 points, giving Microsoft's search engine a 27.4 % cut of the search engine market.
11/02/2011 Report by market researcher Experian Hitwise.
Bing.com by itself accounted for 12.8 % of all searches, a 21 % point increase from December 2010. Searches conducted on Yahoo sites powered by Bing slid 4 points to 14.6 % of the search engine market.
Google and Bing do not use the same alogorithms for their SERP (Search Engine Result Page) and it becomes increasingly important to have your website optimized for all Search engines (SEO).