Very hard to rate a book that depressed the hell out of me. Very well written, excellent character studies and attention to details, really created life in a small town in a real and tangible way. However, there was not one well-adjusted character in the book and I got frustrated at how it just got more and more dark and depressing. A tough read in that regard but good as well. 
 ETA: Now that I have had more time away from this book I am appreciating it more. Yes, the themes are very gritty and difficult, but it's very authentic (not to overuse a main theme of the book). The writing is incredibly skilled and impressive and JK Rowling should be given accolades for this.