To me, this looks a lot like the innovations we’ve seen in the last year or so in Westlaw. Google explains that they are building on the searches others have done and what they’ve found useful. They are trying to differentiate concepts that all my have the same word. ‘Taj Mahal’ is the given example. Does the searcher mean the building in India or the singer or the restaurant down the street?
You can read Google’s press release from yesterday at: Introducing the Knowledge Graph: things, not strings | Official Google Blog.
One big difference? Google is free.