Sofie: My understanding (again, NOT a lawyer!) is that the matter is still highly contested in the USA, since there are still cases in the court system that have yet to set a clear precedent (e.g. ReDigi). For that matter, I'm sure there will be litigation around whether ReDigi's technology is sufficiently different from what Amazon patented, further confusing the issue.

You're probably right that Amazon will have to share some of the profits with authors. Still, that doesn't make me feel too much better. It wouldn't be difficult to provide a "choice" like they have with allowing your eBook to be lent. (If you don't want to lend your book, you can't get the 70% royalty rate.) It's that kind of power that I find problematic for any company to wield, and exactly why I compare Amazon to Wal*Mart.