For example, if a user searches for "San Francisco Bed and Breakfasts," the results will include any establishments that the user's friends have liked on Facebook, along with a thumbnail image of that particular friend.
The feature builds on Microsoft's previous integration work with Facebook, which incorporated specific links liked by the user's friends into a separate results section but did not annotate all results with Facebook data when relevant.
"This is the first time in human history that people are leaving social traces that machines can read and learn from, and present enhanced online experiences, based on those traces," said Lawrence Kim, from Microsoft's Bing social team, in a blog post Thursday.
"As people spend more time online and integrate their offline and online worlds, they will want their friends' social activity and their social data to help them in making better decisions. Integrating with Twitter data 16 months ago was one step, and exploring Facebook's rich streams was another," said Kim.
"If your friends have publicly liked or shared any of the algorithmic search results shown on Bing, we will now surface them right below the result," added Kim.
Microsoft has introduced numerous new features to Bing—such as one-click integration with travel and entertainment booking sites—in recent months in an effort to add value to its search results and ultimately dent Google's dominant share of the search market.
The campaign may be paying off, albeit slowly. Microsoft increased its share of U.S. search results by 1.1% in January, to 13.1%, while Google's share fell 1% to 65.6%, according to the latest data from market watcher comScore.
But Google isn't standing still. The company recently enhanced its Social Search feature so that links favored by the user's friends on sites like Twitter, Blogger, YouTube, and Flickr are prominently featured. Still, Google's own social networking ambitions mean it's unlikely to integrate its results with Facebook anytime soon, giving Bing a monopoly on direct ties with the world's largest social network.
Microsoft shares were up 0.57%, to $26.92, in early trading Friday.