OK, Ian Sane, let's pretend that Nintendo were to show the sequel to Zelda GCN, and say that it had "SpaceWorld Zelda" graphical style. Remember the negative hype when Wind Waker was first shown, well pretty much anyone who had originally said that (even if they changed their mind by now) would go back to what they said and not buy Wind Waker if they were planning on it. They would tell themselves, "ok, well, i can spend 50 on WW now or i can wait till this game, which i would much rather come o r showing now is at least in development." Assuming, they are not a dire-hard Zelda fan (obviously, or they wouldve already bought it), they will wait. I promise you that. Also, games that have already been released are often displayed at shows in general to drum up more support for the game. Believe it or not, that increases the sales for the game.