http://www.bing.com/community/site_blogs/b/search/archive/2011/09/14/adapting-search-to-you.aspx
Ambiguity is a tough problem for a search engine.
You generally search with a clear intent in mind but, without context, the phrase you enter may have a very different meaning to someone else. For example, if you were to type “CSI” odds are you’re interested in the TV show. But, if you live in Twin Falls, you may, instead, be looking for the College of Southern Idaho. When we think about ambiguity at Bing, understanding what your query represents (primetime entertainment or a college in Idaho) is only one step. You may be interested in CSI (the show) but what you’re specifically interested in is this season’s cast, or perhaps you want to catch up on a missing episode. The intent is ambiguous here as well. In fact, over half of the queries issued on search engines are ambiguous to some degree.