According to the filing, each appliance -- such as a DVD player or iTunes app -- need only be discovered once. Discovered appliances would be added to a list of controllable items on the remote's touch-screen. When a user selects a specific appliance from the touch-screen menu, a set of interface controls pertinent to that appliance would appear on the screen. Devices that fall out of range of the remote would be represented by grayed listings.More information and picture at Apple Insider
Apple patents wireless touch-screen remote

Apple recently patented a wireless touch-screen remote control concept that would automatically detect and communicate with existing and future consumer electronics appliances as well as computer systems.