I think it's pretty clear that with the introduction of 3D Touch the home button is on its way out. Apparantly you can get back to the home screen with a "Force Touch" on the 6S and 6S+ so what good is the home button now?
So my prediction is that the iPhone 7 redesign will lose the home button and make the footprint of the devices MUCh smaller. Can't wait. Flame away.
No flame, but I think we're a long way off from removing the Home Button. They can't do it until they have a way to integrate Touch ID into arbitrary places on the screen which I don't see happening anytime soon.