Pottermore: Rowling giving back to the fans

Simon Tall

Tall Englishman
Looks like a way to sell the books all over again to me - this time online and the cynical part of me thinks they will charge for extra snippets that Rowling will include that haven't been in the books before. This way they will make loads more cash sellling something twice.
Ripping off the kids?

Am I being too cynical?