It's coming withing the next five to ten years. All the necessary technologies exist in the lab and will eventually be perfected. LED displays that can be printed on flexible sheets, transparant LED displays -- all things that need no backlight.
And the kicker will be scalable fonts for us ageing baby boomers. Instant large type.
I suspect that audio readers are coming in five to ten years. I suspect that it just a matter of time before there is a standardized format for encoding voice inflections. Famous actors will then licence their voices to "read" any book published in the encoded format.