FANGLAND by John Marks
I know we're all sick to death of vampires, but this is something completely different. FANGLAND has turned the vampire into a much creepier, darker monster, something more akin to a virus that infects your mind and your soul. It's brilliant.
My favourite thing about this book was the representation of the whole vampire mythology, the way Marks took it, twisted it and made it so much better. It's effortlessly creepy, sneaking up on you as you read. I also liked the format, almost as a kind of catalog of evidence, jumping from diary entries and emails, from character to character. It unfolds before you like a case file, the evidence building until it's undeniable.
It just isn't Halloween without a good vampire story and this is a really good vampire story. Read it. You're guaranteed to get creeped out.