Thanks jtenge for the insight info. I also hope they wouldn't do that either, since I think 5711 case size is just perfect for a Nautilus Concept (However, I do feel that 5711 case is slightly thicker and not as wide as of 3710 or 3700 which I feel to be the right slimness/slenderness which a Nautilus Concept should be.)
Well, we'll see for sure in a couple of months!