Google is still by far the dominant search engine in the US, but Microsoft's Bing has slowly been carving out a bigger chunk for itself.
Looking at the desktop search engine landscape in March, ComScore pegged Bing's share at 20.1 percent, finally breaking the 20 percent mark and up from 19.8 percent in February. Yahoo's share dipped slightly to 12.7 percent from 12.8 percent the prior month. And No. 1 Google remained flat with a 64.4 percent slice.
Microsoft has continually tweaked and enhanced Bing to try to lure users away from Google. Last week, Bing updated its image search to help people find more than just photos. In December, Microsoft started integrating Bing into its Office Online product so that users don't need to leave Office to search Bing. And Microsoft has long had a program where it rewards Bing users with sweepstakes and gift cards the more you search.
Though ComScore's numbers include only searches conducted from the desktop and not from mobile devices, Bing's 20 percent share reveals a slow but healthy gain over the past few years. In December 2011, Bing finally surpassed Yahoo as the No. 2 search engine with a share of 15.1 percent and has been gradually moving higher since then.
In 2009, Microsoft and Yahoo entered a 10-year search partnership. On Thursday, the companies announced they have updated that pact, which includes giving Yahoo more "flexibility to enhance the search experience" across mobile and desktop devices.
ComScore's numbers, which were released Wednesday, include only explicit core searches that people manually enter on a Web page. In terms of the hard numbers, Google accounted for 11 billion searches last month, Microsoft for 3.4 billion and Yahoo 2.2 billion.
