The requirement that prohibits an in-app link back to the provider's web store is still there, so you could still see a fight brewing...
Though Apple will seemingly play nice with subscription providers, it hasn't necessary given up all of its control. The company also pointed out in its latest update to subscriptions rules that it will not allow app providers to "link to external mechanisms for purchases or subscriptions to be used in the app, such as a 'buy' button that goes to a Web site to purchase a digital book." Any apps containing such a "mechanism" will be rejected, the company said. Apple was not immediately available for comment.
Read more: http://news.cnet.com/8301-13506_3-20...#ixzz1OmzJRV7l
Here's the revised clause from the policy:
11.14 Apps can read or play approved content (specifically magazines, newspapers, books, audio, music, and video) that is subscribed to or purchased outside of the app, as long as there is no button or external link in the app to purchase the approved content. Apple will not receive any portion of the revenues for approved content that is subscribed to or purchased outside of the app.
Apple appears to have clarified the situation and made it clear that it does apply to book purchases, and not just subscriptions, which was somewhat arguable before.
Note this is also being discussed in the original thread: