Projected capacitive touch panels typically use one or two sheets of glass to create the sensor, which, in addition to the cover lens (also called the cover, window, or glass), can result in a complex structure. Because of this, touch module makers are trying to integrate the sensor into the cover lens in order to reduce material cost, thickness, and weight.
With less layers between your eyes and the display, optical quality should improve. The 3.5-inch Retina Display on the iPhone 4 is already quite fantastic. And to think something better is not too far away is exciting.