I just finished book seven, and I have that feeling that I always get when I finish a nice fat mystery--kind of lost, like I was inhabiting a world and was suddenly sent home. A sort of death, really.
So now I must go through my book pile and decide what's next--but Harry, I must say, is a tough act to follow. JKR filled seven huge books full of history for each character so that a reader is left feeling that they grew up with these people, went to school with them--what an amazing achievement for a writer!
When I grow up I want to be JK Rowling. :)