I liked the overview of the role of the view controllers and the summary of the life-cycle... clear and succinct. The underlying example of his Latin flashcards app is not for me a template for how to best deal with the case of n peer views in an app, as it would lead to some avoidable complications.
The overview of the language however is really just that... a VERY light summary. Someone serious about objective-c would have to read something else to supplement it.