I feel like this is more of a companion-book to the Diary of the Displaced books, which were completely brilliant, than it's own, stand-alone thing. I read this after reading Diary of the Displaced 1-3, and was kind of let down. It's an interesting story, fun to see what happens, and the world the author has created is still fascinating, but nothing as mind-bending as the three main books. The most interesting part, to me, was seeing where this book intersected the plot lines of the Diary of the Displaced books, with both characters and particular settings. It did explain a few things I'd been wondering about.
I would actually recommend reading this, and the other book in set in this same world, Chasing Spirits, before reading the Diary of the Displaced books. Then you'd be coming across little scenes and people from this book and saying "Hey, I know what that is!" or "Oh, that's this guy!"
Worth reading, but really only to either set you up, or help you come down from, the Diary of the Displaced books.