Under the cut to avoid those who haven't read it.
All right. So, we know that Harry "dies" (though not really - it's very brief, and it's really just to clear out the Voldemort dross from his soul and his system).
We also know that after Harry comes back, he wins against old Voldy, right after Neville pulls the Sword of Griffendore out of the Sorting Hat (side note: How did that one happen? Griphook took the sword, so did he give it back, or was this the "fake" Sword from the office which, while not "goblin made" was still sharp enough to cut off Nagimi's head?).
Now, here's my thought:
I don't think Rowling originally meant for Harry to live.
I think originally, her plan was to let him die, which would have taken out the 7th Horcrux. But, because Malfoy was suppose to be the master of the Elder Wand, this means that for Voldemore, it's not nearly as good as his original.
This is when Neville pops in as the true Hero of Prophecy - and why not? Was it not him who organized the troops at Hogwarts while Harry was out on his Horcrux adventures? Was it not Neville who was scarred as badly as Harry - worse, as his parents are still alive?
In the end, Neville could still have defeated Voldemort, become the hero, and Harry would have been the Boy who Lived - only to die for the cause.
I think there was one other plot hole (other than the hat) that's been bothering me - Hermione memory modded her parents so they forgot they had a daughter, so she could fix them after everything was good. Then, later in the book, when they run into the two Death Eaters in the coffee shop, she says that she never did a memory modification but she knows the theory. Plot hole?
Anyway, just a thought running through mah' mind.