Rowling says she will publish Harry Potter encyclopedia
J.K. Rowling has decided not to leave us in the lurch with the small "19 Years Later" epilogue, but will publish a Harry Potter Encyclopedia using many of her notes from the series and story-lines that had to be weeded out of the original series.
She also claims that she will provide
details about the characters who survive Deathly Hallows, characters who continue to live on in Rowling’s mind in a clearly defined magical world.
Hogwarts, for example, has a new headmaster (“McGonagall was really getting on a bit”), and Rowling said she can see Harry going back to give the “odd talk” on Defense Against the Dark Arts. That class, by the way, is now led by a permanent professor, since Voldemort’s death broke the jinx that didn’t allow a teacher to remain in the position for more than a year.
Sounds good, but I am ready to see what Rowling will do next that isn't in the Potter-verse. With every young adult novel out there being touted as "The Next Potter," Rowling should go left field and give us something that no one is expecting.
EDIT: Here is a another article where Rowling discusses Harry and company's future.