According to Allfacebook "On Oct.13th, Bing and Facebook will be making an announcement regarding new search offerings that make search more social. We could see more integration of Facebook on Bing.com. What we do know is that Microsoft plans on deeply integrating Facebook within Bing's search results, making your results more social. This could possibly mean using your own Facebook data to anticipate what exactly you are looking for, providing better search results.
The anonymous data taken from Facebook Links could be populated into Bing, allowing for users to find top shared links, without the need to browse through dozens of search results.
The exact details of the announcement havn't yet been revealed, however we're assuming that the announcement involves further integration with Facebook.