i've been thinking about the title of the book a lot lately.. but i havnt looked at any spoilers because then the would just spoil the book (lol). Any ways at first i thought that maybe sirius was the half blood prince and that since he's dead (if indeed he is) that harry would inherit the throne. But, in the back of my mind i dont want to believe that sirius is dead i mean think about it he went behind the veil and thats it. no one actually saw him die! he could have possibly went back into hiding.... but then again he would have told harry... i dont know its making me all confused... i also agree that neville will start to play a larger part in the book... and the half blood prince could be a new character all together!!! EERGH! i cant wait until it comes out!