Dumbledore Lives - I'm not 100% sure where I read it. Think it was Mugglenet.
But basically the idea is of a similarity between the series and the alchemy process. The alchemy process includes the black stage, the white stage and the red stage. In book 5 Harry was going through the black stage and at the end of the book he lost Sirius (BLACK). This meant that he had passed through that stage and could move onto the white stage (book 6). This is a more positive book but at the end Harry loses ALBUS (meaning white) Dumbledore and will have to move onto the red stage. I think (RUBEUS - meaning red) Hagrid represents this. That's why I think Hagrid will die. It's a lot more complicated than that but that's the basic outline.