Well, if the PC version is complete and they are just waiting for the MS certification, maybe we'll get the PC version early. That way they'll still capitalize on the holiday PC sales.
I remember reading an interview somewhere where they expressed very strongly that they want a simultaneous launch, but we can hope.
Yep, Pete just said the other day on the official boards that they are having them launch simultaneously, no matter what.
I seriously doubt they will change their minds. MS wants this thing out on the Xbox 360 first, not last.