What about e-ink keyboard? Like:
http://phoneverizon.com/2010/downloa...750-phone.html

It would feel better (and use less power) than touchscreen keyboard and it would transform between languages and layouts easier than a conventional keyboard.

It would be a good implementation of four-orientations keyboard, or it could be a usual single orientation keyboard.

EDIT: The major problem would be time needed to redraw e-ink, especially if you switch frequently. But e-ink gets better and better, and there is no need for multi-color, just plain black and white.