Google continued to dominate search, accounting for 72.3% of all US searches in the four weeks ended January 2, 2010, up 1% from a month earlier, according to Experian Hitwise. Yahoo followed with 14.8% of searches, Bing with 8.9%, and Ask.com with 2.5%.

The remaining 66 search engines that Experian Hitwise tracks accounted for 1.5% of US searches.

The number of shorter search queries–– those that average one to four words in length––was unchanged between November and December 2009, while the number of searches of one and two words increased 1%.

During the same period, the number of longer search queries–– those that average eight or more words in length––was down 5% from November.

One-word searches accounted for the plurality (24.34%) of all queries.

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Search engines remain the primary way Internet users navigate to key industry categories: The automotive, business and finance, entertainment, news and media, social networking, and sports categories all experienced double-digit increases in their share of traffic coming directly from search engines.

Bing's percentage of upstream traffic to four surveyed categories––automotive, health, shopping, and travel––increased by double-digits during the month. Google recorded growth in three categories: automotive, shopping, and travel. Yahoo, which recorded declines in three categories––automotive, health, and travel––recorded 11% growth in shopping.