How much is the story influenced by reader suggestions? How much is planned in advance?

Also, was PA being the first character to "speak" and yet being the only of Abby's chums yet to be seen intentional? There's so much tension there, waiting for her to show up, that it manages to fit the tone of the story really well. It's like a horror game. There's always the tension that the rich girl is just around the corner...

And finally, what made you decide to redesign the Sburb machines? It's a small thing, but it really helps to make the story feel fresh and unique when compared to all the other Sburb-ventures out there.