Google and Wolfram|Alpha are providing utterly different services, and as you might expect, that means the terms of use are also utterly different.
Wolfram's Terms of Use are not at all what I would expect from a search engine, probably because that isn't exactly what Wolfram|Alpha is providing. It's a computational service, at least in some cases, providing computational output from various sources of data, one that perhaps never existed until you asked your question. So, they claim copyright on the results and require attribution. That's fine with me, but it is different from what I'm used to from Google and other search engines, so it is counter-intuitive, something to be aware of before I include Wolfram|Alpha output in a presentation on Groklaw or in a book.

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