I am not usually into mysteries, but Rowling's writing has a way of sucking you in that I found myself totally immersed and raptured by the story right from the beginning. 
 I loved Coroman and especially Robin, and the story kept me guessing, you could see the pieces adding up but I was never sure about who the killer was (I did not see it coming at all). 
 Seriously, I will read anything J.K Rowling writes. ANYTHING.