Yesterday I talked about the passing of the once ubiquitous (and in fact iconic) SIGGRAPH message board. This phenomenon of once essential technologies passing into obsolescence has a history as long as we care to go back in human culture. History is littered with discarded or highly marginalized technologies such as the steam engine (both Watt and Newcomen), scrolled parchment, pneumatic tube message delivery, punched card reader, and many many others.
In most cases, the discarded technology was replaced by some specific new technology or combination of technologies: steam engine → internal combustion engine ; scroll → codex ; punched cards → magnetic disk storage + terminal.
Sometimes a technology comes back for one reason or another. For example, even as the music CD is being replaced by its purely software equivalent, the old-fashioned LP is making a surprising comeback, an example of a retro technology being embraced by hip young people.
For any currently ubiquitous technology, such as the automobile, SmartPhone, LCD display, or digital projector, or even an emerging technology, such as the 3D printer, it would be interesting to try to predict what future technology might displace it.
Of course such predictions are often wrong. A lot of people I know are still waiting for their flying car.
I’ll bet the LCD display gets replaced by some sort of e-ink equivalent (you could say OLEDs are already starting to displace LCDs). 3D Printer? Some sort of direct molecular assembly.
I saw a video a while back of a test run (tethered) of the Moller flying car. The ear-splitting noise was one of many deal-killers.