There's a problem with the apparent user experience logic here. By all indications, what Apple really wants (aside from a 30% cut that Sony, Amazon, and Barnes

There's a problem with the apparent user experience logic here. By all indications, what Apple really wants (aside from a 30% cut that Sony, Amazon, and Barnes & Noble will gladly give them in hell) is for users to have a single (iTunes) login to purchase any kind of content inside apps. Problem is, a single login is impossible. In any of the ebook cases, users will have to log in twice: Once to authenticate for iTunes, and once to authenticate with the ebook store – otherwise their new purchases remain orphaned on the iPad and their existing library is stranded in the cloud. So, there goes the UX angle. All that's left is the financial angle Apple can't possibly expect the other ebook retailers to cave on. This, then, leads ultimately to the possibility that Apple simply wants them off the App Store. Which decreases the value of the iPad for anyone invested in those ecosystems. Maybe Apple never wanted them as customers, anyway?