Probably the last set, Chapter 32
Wow. Just....wow. First Fred, then Snape--I have to take a break after every death, and there's so many! Oh, and I don't really think Hagrid's dead, though I could be wrong. I'm reading so fast I'll undoubtedly miss sentences like, 'YES HAGRID IS DEAD YOU IDIOT!' Let alone subtle clues. But I think he did some sort of magic with his umbrella; the spiders retreated, after all.
It occurred to me--the stone--possibly Philosopher's, but I don't know--is probably in the snitch Dumbledore gave Harry. 'I open at the close' is probably the close of battle, or the close of someone's life--Harry or Voldemort's or both. I'm guessing the latter--although honestly they'll probably be fairly concurrent.
I just hope that it's not an excuse to bring everyone who's died back. I /think/ it'll just be a way to get Harry back, but I don't know for sure.
Also, GO NEVILLE! GO TEACHERS!
All right. Now to read the last hundred pages or so.