Nelson US search ranking report of February 2010 has been published on there website.  In February month Bing gained search market share in the United States. According to the search group report market share of Bing search engine was 12.5%.  The following chart reveals Nielsen’s search ranking report for February 2010. Report shows top 10 search providers in United States during February 2010.

The Following figure shows search market share of Google, Yahoo, Bing, AQL and Ask.com from December 2009 to February 2010 as per Nelson Report. It’s depicts that Bing search is continuously growing after a dip in December 2009 where Google’s search market share shows a very little loss during the same period.

I think there is a major influence of Facebook for these changing trends in search engine market share. Facebook increase there traffic significantly in past few months and Bing is Facebook’s search provider.