I've had the opportunity to look at this book for several days and I have to say that it is simply amazing. Not since the APG has a book come out that has something for everyone. I'll break it down by chapter.
Chapter 1: Core Races: This part of the book describes the 7 core race and include a concept which IMO can create great character back story and RP opportunities. That’s the Racial Archetypes - Think Elven Bladesinger from the realms and you'll know what I mean. Finally something that most people in the world can't get but your race. In addition the core races have racial subtypes that don’t change the race stats, but do give flavor by changing the racial traits. Dread Gnome and Gear Gnome come into mind. Finally there are spells & magic items that are primarily used by each race, not exclusively but primarily.
Chapter 2: Focuses on the secondary less fecund races, many of which have been given out as Boons for the Pathfinder Society Games or have been played by fans of RPG games for decades. Fans and Foes of the Drow will be pleased as you can play a drow and work yourselves to becoming 'noble' by spending quite a lot of feats. IMO a balanced approach from what could have been a cheese-fest. There are equipment items which are found primarily (exclusively) in areas where the races are predominant. Some of which are really sweet RP flavor: I'm looking at you Fire Ink (Ifrit Equipment)!
Chapter 3: this continues with the more Uncommon races such as the Sulis, Samsaran, etc. This chapter is written in a similar format to the first two chapters with racial traits/Equipment/special rules all to flavor your character and create more RP opportunities for players. Some of my favorites races included in this were the Sulis and the Elemental Flux vial they can only use which can be both versatile as an player tool but can also be used by the GM to create some fun havoc (you'll see why).
Chapter 4: Was the Race builder where you are given the mechanic behind race creation. Many of the core races and some of the more common monsters were broken down to explain the point creation system. I didn’t tool around too much with this part as I'd rather just pay someone else to create the races for me to play with. But all in all its a simple race creator that doesn’t bog the system down with complicated calculations.
Appendix; This is one of my favorites parts. really you say. well it has something many gamers have been clamoring for years: The Starting ages, maximum ages charts and Height and Weights of the 35+ races featured in this book. How long can a Dhampir or Sylph live for? when do they reace middle age? What is their starting adventuring ages...its in the book!
A great book overall and very well done. This book has something for every player and GM. The Alternate abilities, Racial Traits, and options included in this are sure to make even the most ardent purist eyes light up. So go grab a copy and check it out.