Well, after spending the weekend with Harry Potter and the Deathly Hallows, I'm going to look back at the predictions I made June 5 and see how right or wrong I was.
1. Dumbledore won't come back. I was right, although JKR fudged this a bit. I knew she wouldn't have him be a ghost or turn out not to be dead, but I did not anticipate that Harry would have a vision of him during a near-death experience. I would have respected the story more had she not used this device, but at least there was no pretence that wonderful memories or "you'll always have him in your heart" is just as good as having someone around.
2. I thought Harry would probably be alive at the end of the book and I was right. JKR pretty nearly faked me out though when Harry went to meet Voldemort believing that the only way to end Voldemort's life was to allow himself to be killed. I never addressed the "Harry is a horcrux" theory because I didn't think it was so, but I was wrong about that. JKR tricked her fans by stating early on that Harry's scar was not a horcrux.
3. I thought that Snape would turn out to be loyal and that he had killed Dumbledore according to a previous agreement, to save Draco Malfoy, and I was right.
4. I was positive that Snape had never been in love with Lily, and I was wrong about that. Most of the speculation I read about their relationship had Snape loving her because she stood up for him against James Potter's bullying, and she and Snape were both good at potions. So at least I was semi-right not to attribute his love to that, but to new information in The Deathly Hallows that they knew each other as children, and he always had a thing (a tendre, as Georgette Heyer would say) for her.
5. I thought Snape would save Harry's life, and possibly die doing so. That didn't really happen. I thought he would finally reveal himself as loyal to the Order of the Phoenix, but if he had not passed on his memories to Harry, no one would have known.
6. I thought that Aberforth Dumbledore would do something important. Actually, his importance occurred more in his being a big part of Albus Dumbledore's backstory than in anything he did in the struggle against Voldemort. In fact, he urged Harry to give up the struggle. I also thought there would be a connection between his interest in goats and the fact that a bezoar comes from a goat, but that did not happen.
7. I thought socks would be important, but I was wrong. In fact, socks were mentioned far less often in DH than in any previous book.
As to the JKR hints that I discussed.
1. That Harry had Lily's eyes is important. When he dies, Snape says to Harry, "Look at me." That's because he wants to die looking into Lily's eyes. I think it's in Snape's memories that Dumbledore says that although Harry looks so much like his father, his character is more like his mother's.
2. That we'd learn something important about Lily. I take it we learn that she was the love of Snape's life and Snape's sole motivation for protecting Harry--he cared for preserving the life of Lily's son, if not for Harry.
3. That someone who had not had magical ability would do some late in life. I did not find this. Maybe she ended up leaving it out.
4. Why did Dumbledore have James's invisibility cloak? It was because of Dumbledore's excessive curiosity about the Deathly Hallows, of which the cloak is one.
5. She save one character but sacrificed two others. In an interview she has apparently said that she originally planned for Mr. Weasley to die in Book 5 (I guess when he was bit by the snake). The two others who did die were Remus and Tonks.
6. That Petunia would surprise us. I thought that as Harry's aunt she would finally show some care for him, and she does seem to want to, but she doesn't. The surprising thing we find out I think must be that she longed to be a witch herself when she saw Lily's powers. She only started calling wizards "freaks" when Snape made her feel unwelcome with him and Lily.
I thought that everyone would get a chance to use their expertise in the struggle, but actually most of the minor characters are out of sight during the majority of the story. They don't really get their chance until the free-for-all that is "The Battle of Hogwarts." It is true that then Neville helps Professor Sprout use magical plants, and you do see other professors using their particular specialty. My favorite is Professor Trelawney lobbing crystal balls at the bad guys. During the long run, Hermione does use her rune studies to decipher the story of the Deathly Hallows.
And everyone who thought Regulus Black was R.A.B. was right.