The new Wolfram|Alpha “computational knowledge engine” is fun to play with. My favourite response so far comes from a search for Prince Edward Island:
Assuming “Prince Edward Island” is an island | Use as a volcano instead
While the system is remarkable, I’m sceptical that a resource like this can flourish in the hands of a private corporation. If the policies for data inclusion and curation are not open, the validity of the results will suffer.
They do a remarkable job of showing their sources on any results page – I think the biggest issue they’ll have isn’t that its controlled by a private corporation (Dictionaries and encyclopedia’s do a pretty good job on this front), but the amount of human resources they’ll have/need to add new sources and information to their databases.