Donald Norman
Donald Norman thinks that the next UI breakthroughs are a return to fundamentals (with improvements):

Command line languages
We navigate the Internet by typing phrases into our browsers and invoking our favorite search engine. But more and more, we type in commands, not search items. All the major search engines now allow typed commands, bypassing any intermediate Web pages to directly yield answers. […]
These modern command languages have some major virtues over the ones in the past. They are tolerant of variations, robust, and exhibit slight touches of natural language flexibility.

Perhaps a clue for policy makers in regional areas with lots of mechanical engineering companies: why not position yourself as the leader in the new field of “mechatronics”?

Physicality
The return to physical devices, where we control things by physical movement; turning, moving, and manipulating appropriate mechanical devices.
Physical devices have immediate design virtues, but they require new rules of engagement that differ from what we are used to with the typical mouse movements and clicks of the traditional keyboard and mouse interface. Designers have to learn how to translate the mechanical actions and directness into control of the task.

(via Pasta and Vinegar)