First, I haven't read the book. In fact, I haven't read any of the Harry Potter books at all. I consider them in the same league as "The Lord of the Rings" stuff: dense as lead and as opaque as quantum mechanics. Second, I can still offer a sensible opinion because I'm a character in a novel myself.
So here goes. First, he doesn't overtly DIE. Or at least, you won't see that on the page. That kind of thing requires all kinds of writerly rigamarole that plays hob with the limited observer point-of-view which is probably operating here. It was the same kind of thing with the last episode of the Sopranos where everything when dark. It was pretty obvious that Tony was whacked, but then again, someone could have just as easily pulled a pillowcase over his head as a birthday (or end-of-series) prank. We don't know. The audience was left hanging--and some highly-paid screenwriter is probably fast at work on Tony--Da Movie. So the ending is, well, not really an ending but an Event About Which No Judgements Can Be Made. Or something like that.
Which, is what I predict will happen to Harry Potter in the last pages. At the end of this post I'll even predict what the scene will look like. But first, the rationale.
- Killing off Harry would adversely affect the entire book. Of course, the hype might have already done that, but who really wants to read all the way through just do discover that Harry loses the fight with Lord Baltimore, excuse me, Voldemort. So, if Harry is whacked at the end of this final novel, then millions will buy the book only to jump to the final pages. Which means many will not read the stuff that comes before it. That amounts to 800+ pages of PREFACE to a few sentences at the end of the book. Wouch!
- Killing Harry would send a terrible message to our impressionable youth--that evil triumphs and good doesn't do so well. Okay. That, of course, was the message from the 2000 General Election and any news report that includes the word "Cheney", but must we bring that bummer attitude into the ethereal world of fantasy? Writers write, in part, to escape--and whacking Harry Potter would be like walking from a room with Bush in it. . .to a room with Cheney AND John Bolton in it. Unnecessarily creepy in the extreme. Even Stephen King had happier endings that THAT.
- Killing Harry would effectively end not only the book but the movie franchise. Okay, maybe it's time for it to end, but since movie producers tend to milk the cash cow until only the moo is left---be assured that there are a lot of balding guys with tiny ponytails already planning for the summer 2057 release of Harry Potter XVIII. Whacking young Potter now would make it difficult to sell anything later---even as an alternate-universe version in Claymation. Whack Harry Potter and the Further Adventures of Hogwarts wouldn't even make it as a Toon Boom Express production on Nick.
For those reasons, I think the author will make the ending unresolved--allowing the reader to debate the meaning endlessly, and keeping hope alive for Yet One More Book.
So now for the payoff. How do I predict it will end? Well, the author let it slip that the last sentence involved the scar. . .which makes sense, because it links all of the books. So if the scar is part of the ending, then it must naturally DO something. Now scars can be ugly, prominent or perhaps even glow in the dark, but it's rare that they can DO something. Two things a scar can do is appear---and disappear. My guess is that this one disappears.
So, given that we may have an unresolved ending, I predict. . .
Harry and Voldemort (does this guy have a first name?) fight to the death. Harry finishes off Voldemort (who, following the Star Wars paradigm, is probably some close relative. . .perhaps the postman)--but then mortally wounded, Harry falls to the ground. . .and the scar on his forehead glows, produces a lightning bolt that returns to the heavens-- and then vanishes.
End of book.
Okay, I COULD be wrong. After all, I'm only a character myself and don't write novels--I only appear in them. But given the economics and history of this sort of thing---I'll bet I'm more right than wrong.