I have an issue with the prophecy.
The prophecy is a funny thing, actually. I'ma quote it phrase by phrase, and give some thoughts about each - anybody who hasn't made it to OOTP could probably do with skipping this post (should I white-font?)
The one with the power to vanquish the Dark Lord approaches...born to those who have thrice defied him, born as the seventh month dies...
This, Dumbledore got. It's pretty straightforward. Either Harry or Neville has the power to defeat Voldemort. Surprise.
...and the Dark Lord wil mark him as his equal, but he will have power the dark lord knows not...
This is the single best piece of prophecy-evidence to the Harry-is-a-Horcrux plot point spec. "Mark him as his equal" is not the same thing as "mark him." The "equal" bit is especially telling, to me - how does a scar show equality? I suppose it could just mean that it makes it easy for the wizarding world to tell who he is, but that doesn't cut it for me. Combine that with the power bit, and I read it as Harry will find out he's a Horcrux... and then learn to tap into some of Voldemort's own power, using it against him.
and either must die at the hand of the other for neither can live while the other survives...
The first half is confusing - I can read it two ways. The first is the typical one - one of them has to kill the other one. I'm fine with that. Frankly, though, the first half feels like commentary to me - not necessarily prophetic, just explanatory and, quite possibly, confused. It doesn't even seem to connect that well with the second half (which mentions nothing about one of them killing the other) despite the conjunction. So let's examine "neither can live while the other survives." This sentence doesn't parse like one expects. In fact, one could say it's a lie - it's happening RIGHT NOW (in the book timeline). They're both alive! I actually think this is a symbolic sentence - Harry can't live a normal life while Voldemort survives, and Voldemort can't live a full life while Harry is alive... because Harry contains part of Voldemort's soul, which can't be released until Harry is killed. I think that's the reason "lives" and "survives" are each used - Voldemort and Harry are both currently surviving, but not living. (This is actually a really good argument for Harry surviving the encounter, to turn on myself - it really is a Buffy moment in that sense.)
the one with the power to vanquish the dark lord will be born as the seventh month dies...
Yay for bookends!
The real point is, the prophecy doesn't really say much of ANYTHING other than "Harry might be able to beat Voldy" which, yeah, that's why we read the books. Also, the Neville thing, which is probably a red herring but may not be.
My actual guess is my plot point will come true, Harry will decide to sacrifice himself for the good of the world, and Hermione will figure out some way to save him at the last minute.