It might vary by country and other factors... When logged in to Amazon.co.uk, with one-click turned on, there's no obvious link anywhere near where the product is presented that I can see. A search for "terms" also revealed nothing. A search for "license" revealed nothing. There's a small link saying "Conditions of Use & Sale" all the way at the bottom of the page.

Clicking on that links takes me to a page that provides a very long list of conditions broken out by use and sale. However, searching for "Kindle" or "book" to find out where they are covered, yield nothing. A customer who has been led by the product page to believe the "Buy" button means what it said, could very reasonably assume they were covered by the terms in the "Sale" section.

I think Amazon is threading a fine line here between having courts (at least in Europe) find that even if it might not constitute a sale, terms that deviate too much from the rights a customer would expect under the sale might be null and void, vs. alternatively find that the prominent language indicating a purchase might be illegally misleading advertising if such terms are allowed to stand...

Then again I might just be too hopeful. In the meantime I won't be "buying" any Kindle books.

It wasn't the "1-click" part of the button that was the defense, it was the "Buy with" part. That is, when you actually click the button, it's telling you that are buying it.