Do you ever feel like there aren't enough dragons in the game? I do. The Book of Drakes is a great way to increase their presence in your campaign without drowning your heroes in ROYGBV and various metals.
Playing on the whimsical, the authors of this book have created a rich enhancement to any game world. Don't think this book is just for those who play in Midgard. It has applications in many settings.
There are a couple of errors that popped up in the layout, but nothing unforgivable. The ones that are apparent are text alignment issues, but nothing so horrible as to change the way the rules work.
The artwork in this book is wonderful. Some pictures don't suit my personal tastes, but most of them convey the sense of whimsy, toughness, or wisdom that it's corresponding text is meant to convey. This makes the world of drakes come more to life.
The book is broken into three main parts. The first part of the book contains rules for how a character can get in on all that draconic action. There are alternate class abilities, spells, new feats, an alternate class, a prestige class, and new magical items that any player would find useful. Some things will jump out as silly, such as a fire breathing barbarian, but they're all useful.
The second section of the book is the meat and potatoes, what most people are going to buy the book for. That is the section that contains the stats for drakes. You won't find it until you're about half-way through the book, but once you do you'll be glad you did. There are creatures here to fill just about each of the niches you'd want dragons for. There are odd ones such as the candle drake, which is essentially a flying torch. Others are more dangerous, like the deep drake and prismatic drake.
The final section of the book are rules and templates for building your own drakes. This is quite useful for the budding GM to build a suitable draconic encounter for his heroes to defeat. The rules are similar to rules already available in d20 books, so there won't be anything too unfamiliar there.
All in all, a great one to pick up. I highly recommend that anyone add this to their gaming library if they get a chance.