Amazon had a bit of a rough quarter with a couple of new product launches, and making more enemies at a time like this is not really a good idea. According to Amazon customers questioned, there is a growing number of users that are buying their books elsewhere. Amazon needs to quit playing Apple and work things out or they will be losing even more customers down the road.
The Codex group also found out where those book buyers were going. About half the shifted buying went to Barnes & Noble, independent bookshops, barnesandnoble.com (the online store for Barnes & Noble), used bookshops and Costco, in that order.