It seems the consensus pick for the modern Dr. Spock is Dr. Sears. There's a lot of good stuff here, and I largely agree with his philosophy, although I don't buy into everything he promotes. Much of this book's material is available online on his website, last time I checked, so one doesn't even have to own the book, necessarily.
Dr. Sears focuses on nurturing the newborn. The first big thesis of this book is establishing a physical bond with the baby, which is essential for any new parent. Dr. Sears specifically promotes baby-wearing--slings, baby carriers and the like--which I approve of in theory, although my wife and I never really adopted it in practice. The baby-wearing pitch does get kind of preachy after a while, too.
The book's second big thesis is co-sleeping, which my wife and I wanted to do even before buying the book. We slept with our daughter from day one, with absolutely no regrets. We thought it was very important to have the baby close to us so we could feed her and change her quickly, and calm her down right away, when needed. To us, putting our baby in a separate room would have literally put a distance between her and us, and it just felt wrong--at least to us.
Probably the book's third big thesis encourages parents not to let babies 'cry it out,' which I also strongly agree with. It's an instinct to me, so I can't justify it on an intellectual level. I felt it was my mission to solve what made our daughter cry, and do so as quickly as possible--and I still stand by that feeling. I thought it wouldn't be fair to stand by and let our baby cry in the belief that it's good for her in the long run. It sure doesn't seem good in the short run, that's clear enough to me. For toddlers, 'crying it out' becomes an open question, but for babies, I have no tolerance for it.
I wish Dr. Sears was stronger at addressing common situations with newborns, such as the reasons why babies cry and providing a list of priorities in helping to calm crying babies--information I craved as a new parent. And in the hospital, I was afraid of being clumsy with my newborn, so I wanted a section on different ways to hold the baby, but there's nothing like that here. Those two topics seemed academic to me, so I think the book suffers from their under-coverage.
There were other fairly common issues, such as colic, unexplained cries and pain management, that we were trying to solve with our newborn but could not find fully addressed here. (Side note: Just try to find a baby book that will honestly tell you the doctor-recommended dose of Tylenol to give an infant--I'd bet they all defer you to your pediatrician due to the variety of dosage possibilities. Try calling your pediatrician about an infant Tylenol dose at two o'clock in the morning and see how that goes. I think the FDA needs to better standardize how specific pain medicines are dosed, so there's no confusion, especially with children.)
It was at that point I realized there's probably no such thing as a one-stop-shop baby book. Dr. Sears is a good book by itself, but it's better when paired with another good baby book. Maybe Dr. Spock couldn't be all wrong after all these years.