This is probably one of my favorite comic books of all time, definitely my favorite Batman story. That's saying a lot since I'm not really into caped hero comics.
I give this anywhere between a 4 and 4.5, the main thing I hated about it was that (SPOILER) the Joker's plan failed. Plus, the whole Red Hood thing was a kind of awkward nod to 50s Batman. But there's a lot of good here, a lot of memorable lines. The writing is definitely the strongest point.