Let's get this down on record before Saturday...
In eager anticipation of the final Harry Potter book, I have re-read books 5 and 6 (Order of the Phoenix, the Half-Blood Prince). I've also reviewed the thoughts I blogged as I read Half-Blood Prince the first time two years ago, and I still stand by the predictions I made then. While many readers can't imagine forgiving Snape for having murdered Dumbledore, I believe that Snape will turn out to be a good guy in the end. Despite his being a totally warped character, we know that Dumbledore has always trusted Snape. Other members of the Order believe that Dumbledore has an "ironclad reason" (McGonagall's words) for trusting Snape, even though none of them knows what it is. At one point, when Dumbledore reiterates to Harry that he trusts Snape completely, Phineas Nigellus comments from his portrait "I should think so." So obviously Snape has done something to prove himself. I think we'll find out what that is in the final book. Perhaps we'll hear it from Dumbledore himself, speaking from his portrait in the headmistress's office. It should be noted that Dumbledore tells Harry that he nearly lost his life in destroying the ring horcrux, but for his own skill and Snape's help. Had Snape wanted to kill Dumbledore, he clearly could have done it then. It should also be noted in the end of HBP, when Harry is chasing the Death-Eaters out of Hogwarts and he confronts Snape, Snape could have easily harmed Harry, but he does not. In fact, he prevents others from harming him. What really makes Snape's blood boil is when Harry calls him a coward. I think he's really angry that nobody else appreciates just how uncowardly he has been.
So if Snape is good after all, how do I explain his killing Dumbledore? I think that Dumbledore wanted Snape to kill him. Dumbledore knew that it was going to happen (he knew that Snape had sworn the Unbreakable Vow), and that may have even been what Snape and Dumbledore were arguing about when Hagrid overheard them (Snape saying he wasn't sure he wanted to go through with it anymore, and Dumbledore telling him he must). I also wonder if Dumbledore wasn't going to die anyway, from that awful potion he drank retrieving the locket in the lake. Recall that Harry noticed that Dumbledore was slowly slipping when he was confronted by Draco, but trying not to show it. It may be that there was no antidote, and Dumbledore may have known as much, so Snape may even been putting him out of his misery. Recall that the note from R.A.B. found in the locket said "Dear Dark Lord, I know I will be dead long before you read this…" Perhaps RAB also knew that there was no antidote to the potion.
Speaking of RAB, I agree with the consensus that it must be Regulus Black, Sirius' dead brother. And I also concur with an excellent speculation that I read on mugglenet, that Kreacher helped Regulus steal the locket. (The enchantments protecting the locket meant that no one wizard could get it acting alone, but the boat would only carry one wizard. So having the house-elf as his accomplice is an excellent solution.) It seems a good bet that Kreacher will have more to tell us in the final book. (A confirming rumor: supposedly in editing the latest film, it was suggested that Kreacher be cut, but Rowling insisted that he must not be cut out.) Voldemort would think his locket perfectly protected by a poison potion, as he does not understand that some people on the good side will sacrifice their lives for the greater good.
I also stand by my prediction that Draco and Narcissa Malfoy will be redeemed in the end, and that will be part of the Dark Lord's undoing. In the last book, we saw that Draco was frightened and crying, acting out of fear for himself and his family. And we saw that Narcissa loves her son more than she cares about the Dark Lord, or even herself. Rather an anti-Dark emotion, that love stuff. And Voldemort's blind spot.
I expect we'll learn something more about Aunt Petunia. Has she perhaps got a little bit of magic in her? As to what we learn about Lily Potter and Harry's eyes, I have no idea.
And then there's the big question: Will Harry be killed off? Rumors are flying, and many seem to think so, but I don't. Besides the fact that I just can't imagine she would do that, there are also a few hints from Rowling that point against it. She's said that the last chapter spells out what happens to the surviving characters. She has also long said that the last word of the last book will be "scar", although she recently amended that to say that "scar" ended up not being the last word but near it. So unless somebody else ends up with a notable scar, I figure she's talking about Harry's, as in, his scar disappears, or at least never bothers him again.
So who does die? At least one dear character will die, possibly more. I just don't think she would kill off any of the children (well I guess they're not children anymore, but still). I think she will, however, sacrifice someone very dear. My guess is Hagrid.
So what happens to Harry in the end? Having killed Voldemort, he breaks Voldemort's curse by becoming the first Defense Against the Dark Arts instructor at Hogwarts to last more than a year. The school temporarily closes their last year, as it won't make sense for the kids to be hanging around classes much in the last book, but ultimately reopens, with McGonagall as headmistress and Harry and Hermione on staff. Ron, of course, becomes a professional quidditch player.