If such is the case, are we sure Book is even dead. That gut wound didn't look to bad, I doubt that Mal took Book's body with them to Marand (Planet) and there are ways to fake a person's death to the point where even the doctors are fooled.
I know....I would like to see Book still be alive, but I watched the deleted scenes/special features and at one point when Mal is telling everyone to get Serenity up and running like a reaver ship he actually tells them to tie Book's body to the front of the ship with the rest of the bodies as a place of honor.
I don't know if that was a goof type scene or too deep to put in the movie.
hmmmmmmmmmmmmmmmmmmmm.... I like that line of thought. I wouldn't put it past Joss to do something like that. Look at how many times Buffy and Angel died and came back...