Don't expect high ISO noise improvement, Canon is going for low ISO improvements, better color, things like that. Any High ISO noise improvement will be slight. Of course, the new Digic 6 processor will produce jpegs at higher ISO settings and less detail, but the actual raw sensor output will be a incremental improvement.
The Dual Pixel sensor does have promise if Canon can do more things with it than they have shown on the crop cameras. I suspect that there are some more tricks they can use and are reserving them for the more expensive models. That is the standard sales tactic, whether its a iphone, a new car, a TV set, or a Canon DSLR.