Well, I've given this a good deal of though. The main character, Capt. David Case, will be (one of) my admin characters. He, and therest of the main characters in the story will have 'Legendary' Status. (just means they're special, and didn't start out with the basics like normal characters... Oh, and that they're well known.)
As for how much interaction... Well, I plan on running through the timeline of my story over a course of time. I will play my character, and the other admins can opt to be any of the others... and I would like to roleplay those characters. Doesn't have to be like the book, but same universe, following the same general idea, atleast initially.
So, yes, there will be a lot of interaction with the book characters. The story from the book is basically optional.. however it's the same situation.... also, I imagine that I could have a 'Story' server, and a 'casual play' server... where I'm david case, running around, being David Case. No ties to the book at all.
--Chris