Similar to Google’s Hummingbird update, Bing is rolling out an improved conversational search feature. Bing is trying to “keep the conversation going” by providing results to conversationally relevant searches.
For example, if you searched “who is the president of the united states?” and then follow that with a search “who is his wife?” the second query will be based on both searches and the results will show the president’s wife.
I’ve tested this with a few different searches and it’s not perfect, but a very cool feature Bing has.