Ben Brooks on Apple’s IAP subscriptions reversal:

This is actually a pretty big deal because […] I am pretty sure this means that Amazon can keep the Kindle app the way it is — they may just need to remove the link to the online Kindle store from the app. Though I am not 100% on this just yet.

The bold bit in the quote (my emphasis) is the one thing a lot of people are currently mulling over online. My guess: Apple will eventually either allow or tolerate a storefront link, but not a direct link to any particular single product or item that you can otherwise buy in iOS. It’s one thing to piss off Apple by saying “hey, buy that on our site for less money and stop Apple getting a cut” and another entirely to say “oh, by the way, our store’s over here, if you fancy browsing for a bit”. This is especially so when it comes to things like Kindle, given that Apple’s IAP infrastructure wouldn’t be able to cope with even a fraction of Amazon’s inventory anyway.