-The title is going to be Harry Potter and the Order of the Phoenix
-There's going to be lots more stuff on Lily Potter, including info on her maiden name.
-Why Voldemort hunted down and wanted to kill Harry's parents will be revealed.
-Former Professor Remus Lupin will return and be one of the main characters in the book.
-The real Alastor "Mad-Eye" Moody will return as well.
-Harry will become the new Quidditch Captain for Gryffindor!
-Hermione becomes a Prefect!
-Hermione visits Viktor Krum over the summer in Bulgaria.
-One of Harry's friends/or fans will die.
-Sirius Black will be another one of the main characters.
-Professor Snape will pretend to be a Death Eater & rejoin Voldemort's side again, but actually just spy for Dumbledore (remember how in the Pensieve(Bk. 4), Dumbledore said how Snape turned to their side & spied for them before Voldemort lost power, and how in the end of Bk. 4, Dumbledore was all mysterious & said to Snape you know what you have to do..and Snape left).
-In all future books (starting Bk. 5 and on) J.K. Rowling said she will write more complicated, harder, higher level, and darker books, so maybe it's directed at older people now?
-Fleur Delacour will become a teacher at Hogwarts (remember how she said, "I am 'oping to get a job 'ere, to improve my English," Bk.4-pg.628)
-The new Defense Against the Dark Arts teacher will be female (maybe it's Fleur?)
- At the end of book 4, Dumbledore tells Sirius to round up "Remus Lupin, Mundungus Fletcher, and Arabella Figg...The 'old crowd.'" Well, Arabella Figg COULD be the very Mrs. Figg who lives on Privet Drive...Plus, at the Quidditch World Cup, Harry DOES mention how the tents smell like Mrs. Figg's house...An obvious case of foreshadowing. This rumor was passed to me by Becca, Thank You!