As I write this, there is something very wrong going on with the Apple App Store. Apparently, as you can see for yourself, most of the top books apps at the moment all come from the same developer (and seem to be crapware). A situation supposedly driven by some (large scale?) iTunes account hijacking.
Right now we're still in the dark regarding how this was possible and Apple is already looking into it. What's curious, however, is that the growing flow of people reporting unusual activity on their accounts don't see these book apps on their bill. Are these only the first signs of a bigger issue? We don't know. In the meantime, our recommendation to everyone is to change your iTunes password.
As usual, we'll keep you posted as the story unfolds.