I think that this book is hands down the best medical source for parents of all the baby books I've gone through, and I've gone through plenty. However, I think that Dr. Sears greatly undersimplifies children's behavior, which I found very irritating. It just seems like the answer to EVERY behavioral problem is AP! And that just isn't the case. Children are more complex than that, and you don't even have to be a doctor to know that. For example, he talks about how much better babies sleep in "the family bed." My baby never ever wanted to be anywhere but his own crib, and to this day will ONLY sleep there.
Another thing that bothers me, and I know some here disagree, but Sears takes the hard-line on nursing, childbirth, attachment parenting and nutrition, but I feel that he wimps out when it comes to forming an opinion on daycare vs. at-home mothers. If you're going to express your opinion on everything else, why not this? (By the way, many mothers who stay at home do it because they believe it's the right thing for their child, and end up scrimping and saving, and NOT because they have loads of cash from their husbands' income!)
This is the bottom line: my advice is actually to buy this book. For me, the medical information was and is invaluable. Unlike a lot of these other reviewers, however, I never felt like a "bad parent" for not doing everything Dr. Sears recommended. I feel extremely secure in my abilities and instincts as a mother, so I really didn't care if I got the feeling that Sears would think I was doing my child a disservice just because he always slept in his own crib. If you can ignore this kind of thing too, I think you will find this book to be a great resource in other ways. One thing he says in this book is absoultely true, even applied to his own advice: if it doesn't feel right, DON'T DO IT! Remember that when you read this book, and don't be intimidated by the AP style if it's not for you.