I remember talking to a friend once, who asked me if I thought Joanne Rowling would "let Harry be" after finishing the seventh book and thus completing the saga. My honest reply was "yes". That was before the final book was released, mind you, so all I could do (as a hopeless Harry Potter fan that I've been over the past six years) was think about the end of the story, and didn't give the "Harry Potter going on" theory another thought - until this very day, when this particular piece of news came in. It seems that Rowling simply can't let Harry be - seeing how she seems to keep finding pretexts to add more and more to the already impressive amount of texts that makes up the boy wizard's magical world.
First it was a book about the magical sport that wizards play, Quidditch, then a book about the fantastic beasts featured in the stories, then a book of wizard children's stories - and while none of these were directly about Harry, Rowling has just taken this a step further, by claiming that she may consider a revival of the whole Potter universe and the Hogwarts, the magical school for witches and wizards that was at the center of the action for almost the entire series.
However, Rowling expressed her belief that the future story will not center on reprising the story of Harry and his friends. "There have been times since finishing, weak moments, when I've said, 'Yeah, all right,' to the eighth novel. If, and it's a big if, I ever write an eighth book about the wizarding world, I doubt that Harry would be the central character. I feel like I've already told his story. But these are big ifs. Let's give it 10 years and see how we feel then".
Personally, I have a feeling it will take less than 10 years for Rowling to go back to writing about her beautiful magical world and its characters. And no, I don't think that if she came back to it (even with a different story line) she would do it for financial reasons - let's not forget that Rowling is richer than the queen of Great Britain and that the final two movies in the franchise haven't even hit the screens yet. But I do believe that writing the Potter saga was an amazing experience for its author, pretty much like a drug addiction, only in a good way this time. It's hard to keep yourself from writing more of the good stuff - or reading it!