in china the most popular search engine is baidu ,the second is google, so few people use the yahoo search. so how about the yahoo search in america?
Yahoo holds about an 18% market share of searchers in the USA as of Sept. '09. http://www.techcrunch.com/2009/11/16/bing-10-percent-search-shar/ However, both sources show the upward progression of Bing, which could very well overtake Yahoo this year. http://gs.statcounter.com/#search_engine-US-monthly-200901-201001
I think that search engines are the most popular google. then the second order is yahoo. i do not know about search engine Baidu.