I have one last idea I want to share before the release tomorrow. If Pottermore IS a MMORPG, online game, as leaked reports seem to suggest, I don't think it will be set exclusively, or perhaps even mostly, in the seven-book series. With JKR's apparent active involvement in the project, and her name attached at every point, I have a feeling she's found a way to give her fans all the backstory and future-story of the wizarding world without having to write a prequel or a sequel. She could have written the storylines for the game, and some, at least, of those lines could focus on the Marauders, Voldemort's early years, James and Lily's marriage, Dumbledore's days with Grindewald, and you name it. Looking forward, if she wants to firmly stomp out any possibility of doing a new series set in the Potter world, she could have written active storylines involving the next generation.
I'm still hoping for an encyclopedia component, but that could be used as tidbits of information throughout the game.
So there it is, for what it's worth. In a little more than eight hours, we'll all know. But this has been loads of fun and has kept me from cooking and cleaning! :-)
I'm off. Will be here in the morning for the final reveal, blogging and Tweeting away. Join me!