If you’re going to consume content on their device, Apple would prefer that you buy that content from them and not from a competitor.
Or if you do buy want to buy it from the competitor, that’s okay, but then there’s a corkage fee. Only you don’t pay the corkage fee, the competitor does. (Well, unless they pass off the extra cost to you.)
Can you read iBooks on the Kindle? What about Sony’s books? Nope.
It’s neither complicated nor evil. It’s business.
I disagree with MG Siegler’s point. The whole idea behind the iPad is that it isn’t a single use device. Comparing it to the Kindle or Sony Reader is disingenuous. People purchasing the Kindle never expect to be able to read iBooks content on it. The iPad on the other hand is the do many things device as highlighted by their own commercials. My problem is that it is both complicated and a little evil when Apple tries to lock out entirely any and all means of content purchasing that doesn’t go through itunes. It’s analogous to when Sony fucked up their Digital Audio Players by making them compatible with ATRAC files only and not MP3’s or if the iPod had only allowed music purchased from itunes.
It’s perfectly fair for apple to only allow in-app purchases that use itunes which forces Kindle, Nook, and Zinio apps to shift purchasing to a browser based solution which is far less elegant but to now require the use of itunes in-app purchases does nothing for consumers and a great deal for Apple.
Let’s see how this develops.