In the area of cases, how about a sensor which can sense a fast increase in acceleration and therefore deploy some kind of impact absorbing contraption.
In the area of charging and battery life. I envision a world where one day wireless emitters of electricity, impervious to us, charges all devices everywhere wirelessly, most likely based on solar ray harvesting or electric field manipulations. Batteries will virtually cease to exist, at least in the public mind.
In the area of usability and feel, see the iMorph video below if you havent already
Of course all the internet capabilities, WiMax, Wifi, 3G-4G (or something crazier). 8Megapixel camera with flash and DVD Video recording.