I looked through a copy a friend ordered and these were my thoughts.
First, I want to point out the positive. Because it is mostly positive. I think it is one of the better books in the series, far better than either of the Ultimate Books, right there with the APG (and in some ways better). When I got home from my friends, I immediately got online and ordered a copy. It is something I want in my library and on my shelf for my players to access. It is something I want to access. It made me excited about starting a new campaign just to play with the new concepts.
Which is exactly what it should do.
I was very, very skeptical about the whole venture. I was wrong, they pulled it off. The devs seem to have hit the right tone of variety rather than power on what I have read so far, and I really like the added options for each race. It is a book that broadens the world of options, rather than creating “must have” shiny tricks. I read it imagining lots of new ways to approach things I wanted to do that were previously difficult to do. It didn’t seem to “break” things, but rather it seemed to “allow” things that were hard to accomplish before. The choices were actual choices, with sacrifices and trade offs.
On the less positive side...I wish they had clearly separated “advanced” races in the featured and uncommon section. Some races are just, factually better. They aren’t unclear about this in the core race example section. The core races are between 8 and 11, a small variance that doesn’t much bother me. I would call that within the margin of preference.
Aasimar are 15, almost double the lowest core race. Drow are 14, but with some of the weaknesses I am ok with that. However Fetchlings are 17 and Suli are 16.
Tengu and Vishkanyas are 13, and I can live with that considering the drawbacks of the flavor, but Svirfneblin are 24. Three times the lowest core rase.
I want the options, I don’t want to reduce the number of options. But I want them labeled appropriately so we don’t have messageboard arguments about cruel GM’s who won’t allow my Svirfneblin with a heart of gold PC. I want the disclaimer to be very clear that certain races are better, and I would have liked some kind of accommodation system to address this. For example removing the first level feat for Suli and Aasimar, and perhaps even making the Svirfneblin a +1 CR.
I don’t worry about this too much at my table, but one of the goals of upping the power level of the core classes from 3.5 to Pathfinder was to make sure the core was still the primary. When you have races that are unquestionably better than the core races, and you don’t have any penalty for playing them over core races, that is a problem.
I don’t want the options removed, but I also don’t want a world where GM fiat is the line between everyone being a “rare” race.
But at the end of the day, I ordered it as soon as I got home. Which is about as good an endorsement as I can make.