Well, Rowling has said that it would be possible, but this book would not have harry potter as main character....

For me, this sounds like and Albus Dumbledore book... you know, we will know everything about him before harry potter.

I'll be glad to know everything about him in hogwarts as a student, his "friendship" with Griendelwald and the battle...

what do you think?

All I can say is that it will be out next year and there'll be at least 4 more.

and it will be a released exclusively over xbox live

Actually I think it'd be more likely to be prequels. There was a lot of history to the whole HP series, so it wouldn't be surprising if she could easily squeeze a few books out of that alone.
Personally, I'm still a little irritated with Rowling over the whole "Dumbledor is gay" deal. Not so much because of him being gay, but in the tardiness of the announcement. Sorry, too late! Series is over so I don't care if you're the author, it's not cannon. Seriously, no mention was made of it through the entire series, or even any allusion to it, so why mention it now?

anyway, that's just me venting, so please try not to get wrapped up in that point and snowball it into a huge flame war that gets locked.

It'd be cool if she did a prequel about the original Order of the Phoenix.

I'd probably buy it... but I have grown bored of the books now... I am eagerly awaiting the next installment of Lyra from His Dark Materials though... I read Lyra's Oxford but I want to know more.

 and about the first war

 Has another one been announced?

I'm waiting on the third eragon book to be announced

I thought it was being written as we speak.
And I don't kike Eragon personally, a bit "meh"

Hmm, I never really got into the potter books. The story was interesting, but I hated the writing.
If a prequel was released I might pick it up, might spark my interest for the other books.