We're probably going to see more usage of touch screens on high production items as costs continue to come down, particularly in more complicated devices, but buttons/knobs are never going to go away. I mean, are you really going to install a processor with screen and write a GUI for everything? It's simply not practical unless you're dealing with an electronically complex device with high production numbers. For everything else, it's going to be buttons, switches, knobs of some sort.
-Hans