So, I bought the book this afternoon, and, (taking a short break from reading other books), finished it in three hours. Here's a brief spoiler-less review:
It was a good book, certainly, but I found it somewhat unsatisfying. I'm not sure why - I just felt that the story was a bit thin. Maybe it's because it's a YA book, but I've read many YA books that didn't leave the same feeling, including some of Gaiman's other offerings. It's just - well, the book is mostly about the boy growing up in the graveyard, his interactions with the ghosts, and the mystery of why his family was killed (this is not a spoiler, the book starts with the murder). By the end of the book, I sort of felt that we were given glimpses into the life of the boy and into the graveyard - and what was there, was really, really good - but not enough to give me a real sense of either; and the mystery, well, it's alluded to vaguely a lot and then explained in an infodump or two. At the end, there was a sense that the real interesting stuff as far as that subplot went all happened in the background.
So overall, it's was overall really good, but just not quite enough of it.