I really enjoyed this book. I thought it was well written, easy to follow, and did a great job covering all the major aspects of iPhone programming. This book also does a great job showing how to create a lot of different kinds of apps (from weather to TableView, etc.). The author also goes through how to interact with some of the iPhone hardware, including the GPS.

As other reviewers have mentioned, this book really shines in helping the reader understand the iPhone memory management philosophy. I'd highly recommend this read to anyone trying to begin iPhone application development.