December 2007, 66.2 billion search queries were conducted worldwide and Baidu.com Inc. was the third ranked search property worldwide with 3.4 billion searches, capturing 5.2 percent of worldwide search share.

Top search engine WorldWide www.google.com and all its web properties.
Top search engine in Russia www.Yandex.ru
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Top search engine in China www.baidu.com or www.baidu.cn
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Top search engine in Korea owned by NHN www.naver.com
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Source Comscore.com