*Harry will leave Privet Drive early again, for a "much pleasanter" reason than in book 5.
*The opening chapter of book 6 was originally planned for the early parts of book 1, perhaps we get a more in-depth story of what happened the night Harry's parents died.
*Neither Harry or Voldemort (including Tom Riddle) are the Half-Blood Prince
*Arthur Weasley will not be the new Minister of Magic
*By the ends of books 6 and 7 "you'll have all the back story you'll need", says JK Rowling, and a prequel will not be necessary
*There will be a new Minister of Magic, no more Mr. Fudge.
*We will find out what happened to Hagrid's half brother Grawp. He will be a bit more controllable in book 6.
*The Dursleys are in the next book, but Harry's stay with them will be the shortest yet. In book 5 he stayed for 4 weeks, so we know his stay will be less than 4 weeks.
*Cho Chang will not be a romantic interest of Harry in Book 6, however there will be a "little romance" for Harry says JK.
*In books 6 and 7 we will find out exactly why JK killed off Sirius.
*Harry becomes even more powerful in book 6.
*In books 6 and 7 we will find out why Dumbledore trusts Snape.
*We will find out what happened to Wormtail AKA Peter Pettigrew
*More about the animosity between Snape and Sirius will be revealed in the last 2 books.
*JK has said that giving away the form of Snape's boggart and patronus says too much. We'll definitely find out what Snape's worst fear is, and it'll be important.
*Hermione and Draco will NOT end up together in book 6 or 7.
*We will find out what exactly Dudley saw when he looked at the dementors.
*The reason Voldemort and Harry both didn't die when Voldemort tried to kill Harry, will be revealed.
*We will see more of Draco's mother, Narcissa Malfoy, now that Lucius is busy.
*We'll learn more about Harry's scar in the last 2 books.
*Moaning Myrtle will make an appearance again, as will Tonks.
*More about Voldemort's birth will be revealed, thus helping us understand why he is so evil.
*Muggles begin to notice "more and more odd" occurrences in book 6, says JK.
*The wizarding world is really at war in the sixth book.
*Harry will tell his dearest friends about the prophesy after it sinks in to him.
*We will learn more about Harry's relatives, including his grandparents (though JK says they aren't really important to the story)
*We will find out what happened to Sirius's motorbike.
*Book 6 will be shorter than the 5th book (or at least JK's 99% sure, but will not swear on her children's lives)
*There will be no "new" nationalities of children at Hogwarts. Hogwarts is a British school, and JK says that adding foreigners for the sake of it is not in her plans.
*During an interview, when JKR was asked in which Hogwarts room she'd like to be for 1 hour, she said it would be a room in which Harry has been before, but doesn't know its importance. Yet. (this could have happened in book 5, but we're unsure)
*It's very important in the plot that Harry has his mother's eyes, and that her wand was very good for charms.
*During an interview for Kids BBC, Victor Greensteet (reporter) asked Rowling if Harry would have a dragon for a pet. This is what she replied: "You can't tame a dragon, no matter what Hagrid thinks. It's simply impossible. So no. He has more common sense. He MAY have a different pet in the future, but for now, I won't say anything else". (This could have been buckbeak, but I'm sure we can expect more pets)
*In the same interview for Kids BBC, the reporter asked J. K. if Harry had ever used the internet, and this is what she had to say: "No. They (the Dursleys) won't let him go near Dudley's computer, and Dudley is the only one who has a computer. They hit him if he gets too near to the keyboard. So the answer would be No. I use it a lot, but Harry doesn't. Wizards don't really need to go on the web. They have an even better way to find out what's happening in the outside world, which I think is a lot more fun than the Internet, but I'm going to keep quiet on this one."
*The choice between what's right and what's easy will be a pillar of the plot in Harry's last 2 years at Hogwarts
*Harry's parents' profession will be a big part of the plot.
*Something HUGE will be revealed about Lily Potter.
