In May, Bing underwent a big facelift, including a social sidebar in its search results.
That sidebar included Facebook integration, showing actions your Facebook friends have taken related to your search query — that section is called “Friends Who Might Know.”
The social sidebar also included a section called “People Who Know,” with information from experts and enthusiasts related to your query search, culled from Twitter, Google+ and the blogger blog-publishing service.
Now, Bing is integrating foursquare into the “People Who Know” section of the social sidebar.
If you search for information on a hot restaurant in town, for example, tips and recommendations from those who’ve posted publicly about that restaurant on foursquare will show up.
The rollout starts today in the U.S., according to a Bing blog post.