Predictions
Okay, just to get my views on the record:

Spoilers from England should be out by now. I have no interest in checking. In fact, I'm going to have to wait for my book from England (to avoid the American re-writes), so I'm going to be vulnerable to spoilers for a couple of weeks, I should think. Anyone who spoils it for me will be shot. What follows are my guesses.

SNAPE
What should happen: I'm conflicted between Dumbledore being right and wanting to finally crush the hopes of everyone who wants to believe that he's a good guy against all evidence. Back when he was still viewed as a bad guy (up until the end of Philosopher's Stone, basically),
What will happen: I'll have to go back and re-read the end of Half-Blood Prince to see exactly what proof we have that Dumbledore is dead. I suspect that this will be the lesson about giving everyone a chance and the guy you love to hate and pick on being a good guy. Dumbledore arranged for a very convincing fake death to let Snape re-infiltrate the Death Eaters without getting himself killed for his previous betrayal. Snape possibly dies a heroic death saving Harry at the end.

DUMBLEDORE
What should happen: He comes back. They always do.
What will happen: He comes back. See also under "Snape."

HARRY
What should happen: Harry needs to die, regardless of whether or not he comes back to life. It's the really obvious ending, making Harry a Horcrux and all.
What will happen: Either the author wimps out entirely or he dies and comes back to life.