The book is now being revised for iOS 5 and Xcode 4.2; these are the code examples, as revised. For the new version of the book, see http://shop.oreilly.com/product/0636920023562.do. Selected chapters from the revision draft text are also available at http://www.apeth.com/iOSBook/. About the first 750 pages of the book have been revised for iOS 5 so far; this edition will probably run to 1000 pages, so we're about 3/4 done.