I had read a lot about the ballyhooed launch of Wolfram|Alpha. It was designed by a scientist. I read about how it was going to give Google a run for its money. Well, I've looked at it and I think Wolfram|Alpha and Google are two totally different animals. Wolfram|Alpha should be used for finding answers to questions, particularly scientific questions like formulas, technical information and stuff like that. There outcomes are in the forms of graphs, charts or diagrams. Very scientific. Don't use this site trying to find a wide range of information on social sciences subjects or the humanities. This site will give you "vital statistics" on people, places dates, etc. Use Google, hakia or Grokker for social sciences and humanities information. It's a interesting site in terms of giving you "almanac" knowledge.
When I typed in my fav search, Henry VIII, I got this. You can tell Wolfram|Alpha was designed by a scientist and not a historian.
Check out this site. It is interesting. You really need to use it to really see what it is built to do. It gives you some sample topics to see what it will do. Know that this site is out there, but know when to use it and what it is for.