I would like to add one idea that still falls strictly under the keyboard project but still doesn't seem to be mentioned: there should be additionals buttons at the edges.

The N900's Shortcutd has been so nice, and IIRC it is only able to use the camera button. (Btw, one camera-button would be nice as well, with the ability to half-press it, super-nice if that could be used in the camera application and let the volume buttons do cropping/zooming lke in N900.)