As you probably know, the SFWA (Science Fiction Writers of America) is a professional organization for authors of SF and fantasy. A lot of authors have a page on the site with a list of their books and link to where you can buy them. As of today, those links aren't going to include Amazon (unless it cannot be avoided).
Here's the relevant part of the announcement:
While Amazon has the right to decide with what company it does business, its removal of many of our authors’ books from its ordering system will have an economic impact on them. Our authors depend on people buying their books and a significant percentage of them have books distributed through IPG. Therefore, SFWA is redirecting Amazon.com links from the organization’s website to other booksellers because we would prefer to send traffic to stores where the books can actually be purchased.
This isn't the big 6 publisher that I predicted yesterday, but it's still not a small story. And what's even more interesting is that the SFWA made this decision yesterday.
Yes, they made this decision before most of us were done writing up the EDC story. If you were wondering how much Amazon has pissed people off, that should give you a clue.