First off, I'm a huge fan of Pathfinder. But I'm not a fan of "Ultimate Wilderness." There are a number of issues with the content in the book, mostly the clarity of language. A lot of the rules seem unclear and not straightforward. The shifter is the biggest example of this.
To be honest I was looking forward to the shifter, being far more robust than it actually is. And I understand that this is my issue with what I expected from them, but what built up my anticipation of the shifter was the quality of past classes released by Paizo: summoner, alchemist, witch, bloodrager, investigator, brawler, spiritualist, medium (even if it isn't harrowed), magus, ninja, hunter and so on and so forth.
Past that, I'm not a big fan of the reprinted material because I buy the smaller books. If I'm buying the smaller books why would I want to buy them again with a hardcover?
That being said, I'm still a big Pathfinder fan, but I'd like for future releases to take a different developmental cycle than what "Ultimate Wilderness" received. This book seems like it lacked editing and playtesting.