A very good read. I'm glad I stuck with it, because I was about to give up in the first couple of chapters, which are very "OK I GET IT" about how sad this boy is that his mom is dead. But then once his dad gets in a new relationship and they move to a new house, things really pick up steam and I couldn't put the book down from there on out.
Actually the book would have moved a lot faster if it'd just started there, and then done some backstory on his mom dying, and therapy, and the resentment about the new family. Anyways.
Thematically, this book treads very similar territory to Pan's Labyrinth. And I don't know if we've talked about Pan's Labyrinth, but FYI I hated it, and this was much closer to what I'd hoped PL would be like. Not 100% there, but closer. I felt like the mythology was much better developed, and I liked the ways that the fantasy world tied in with the real world much better. (i.e. it's not necessarily "all just a dream" which is the worst ever.) (but on the other hand there wasn't total crossover between the two worlds either, which is what I always want.)
To sum up: not perfect, could have used some editing, but I liked it.