Pentax's removal of the tethering capability in the K7, K5 and 645D makes absolutely no logical sense at all. Publishing and supporting an API or an SDK would certainly make sense. Let third parties support this capability - especially with netbooks, tablets and smart phones. This would be a natural evolution of the product, especially since they probably will not support moveable rear monitors on the camera bodies. This would be a wonderful equalizer for macro work and other types of photography.
Extending on the CHDK idea, Pentax could certainly very easily add some of the functionality that CHDK offers - lightening detection, Motion detection, extended time lapse, etc. Being able to disable DFS on the K5 was a start, along with the Astrotracking GPS (if only the reports would show it working better). Anything that would add to the Pentax community of users. Give folks good reasons to come to Pentax.
However, this requires Pentax to actually follow through. With Pentax USA really unable to do anything on their own, and who knows what Pentax Japan (now Ricoh) will listen to, its somewhat of a crap shoot. Add some cool capabilities, attract the open source folks for out of the camera support - think outside the box!