Not porn. Nor anything like that. But because in one of the chapters, they mention using Amazon to do a search for titles in order to find appropriate genres for their submissions.Apple Made Its Decision. My Turn
Holly Lisle, a writer of fiction and help novels for writers created a new novel, How To Think Sideways. They had a problem with one of the chapters- it had to do with links to Amazon. So she resubmitted, taking out the links, and now it has to do with content that mentions Amazon.
We had a discussion on DC before about the precedent of letting distributors determine what content was suitable to be distributed, and I had an idea that even though it was porn at the time, that approach seemed fraught with danger... and now that danger has arrived.
She makes the level headed and rational point that this isn't really censorship, as only the government can censor. But, for all intents and purposes, it's not very far from that point, IMO.