First, and most importantly: I read this book cover-to-cover, and I expect it's prepared me well for the General Class exam. It covers all of the material on the exam and includes a copy of the question pool in the back. The text includes references to the relevant questions, and the questions in the question pool have references back into the text that covers that material. There's an online version of the question pool where the questions match the order of the text, so that's a little easier to use. Between all this and an iPhone app that generates practice exams, I feel pretty good about the exam material.
There are several editing errors, but most of them are documented in the book's errata on the ARRL web site. (In a few cases, the examples in the text are actually wrong, which can be pretty confusing.) The coverage of some topics feels cursory -- just enough to answer one or two questions on the exam, without really conveying much understanding. In some cases, concepts are used before they're properly introduced (e.g., SWR, though admittedly you're probably supposed to know that from the Technician exam).
The book is very focused on the exam material, and other topics that seem useful to know aren't well-covered. (For example, between the various chapters, you can probably put together the things you would need to get started with an HF station, but it's scattered around a lot. It would be useful to cover specific suggestions for getting started, such as a list of all the components you need.) I think some of this is covered in the ARRL Operating Manual instead.