While many U.S ratings services say Yahoo is America’s second leading search engine, Microsoft might prefer the results of Chitika’s latest rankings. Chitika’s July search stats suggest that Bing has beaten out Yahoo for the No. 2 spot in search market share, and marketers may want to plan paid search campaigns accordingly.

Chitika says that Bing accounted for 11 percent of the search market last month, while Yahoo represented just 6 percent of last month’s traffic. Microsoft may be celebrating and Yahoo could also be pleased – the company has started transitioning some of its searches to Bing in preparation for the upcoming alliance between the two. (Still, Yahoo has recently explained it will continue to focus its efforts on search.)

But before the celebrations begin, and before marketers consider shifting their paid search ad spend, it may be worthwhile to examine how Bing’s success was measured. Chitika ranks search engines according to “the percentage of all search traffic coming into the Chitika advertising network in a given month.” It could be that Yahoo actually accounts for more searches than Bing, but fewer of these queries direct users to third-party sites in Chitika’s network. Hitwise and comScore’s latest search engine rankings each place Yahoo second in terms of search market share.

Regardless of which search portal takes the silver prize, all rating services put Google in the lead. The Chitika report shows that Google accounted for 80 percent of search traffic last month. As it holds tightly to the keys to the search kingdom, the search giant is making it easier for small businesses to benefit from advertising on Google. From the release of new features that let SMB owners respond to reviews on Google Places to the recent launch of Google’s Small Business Blog, it seems the site is becoming more SMB friendly, and it is proving as powerful as ever in catching consumers’ queries.