I'm pretty excited for this, not just for myself, but for our daughter. She has been way into Harry Potter for the past year plus (she was Hermione for Halloween last year), and it is great there is potential for her to be able to see the new movie(s) on the big screen since she was too young for the proper Harry Potter.
I'm also with you guys on wanting more books. I've been reading the Potter books to my daughter before bed each night, and it would be great if there was more for her to get in on the ground floor with. I know she's even asked me before if they'll ever do "the adventures of their kids", which would be kind of cool. Either way, I think it is exciting news just for the fact that we get to return to that "world". Sort of when they finally announced that the Hobbit was moving forward, I'm just excited to get to experience that universe again in a new way. I really get the feeling that they'll try to branch this out in the "Marvel Model" like Star Wars is doing, and like WB should be doing with DC.