Going by the prophecy made, it will either be:
1. Harry dies - which to me is pointless cos it would have all been for nothing. Which also means that Voldemort would have succeeded with what he initially wanted. His "equal" being no more so the evil would continue. The saga ends here.
2. Voldemort dies - which is good. Harry would obviously still be alive and the world would be rid of the evil Voldemort has spread. Then JK would have to continue writing or she will have to have one heck of an ending to the plot.
or,
3. Both dies. This could be a well possibility! It would end right there and then.
What do you guys reckon?