I just got the book and browsed through it. There are two topics I struggle with in general and couldn’t see addressed in the book.
Let’s say I want to have customizable menus where the users can define or change the content (aka drop down list boxes). In this scenario I would prefer to store it in a data store and not in a NIB. A simple example would be the life cycle of a ToDo. The values new, in progress, and complete could be added to with postponed, awaiting response, or alike. Additionally, how to handle this in multiple language using core data is interesting for business software at least.
Other than that the book seems to cover Core Data pretty good. I like both the style and content so far! Look forward to the complete book!