Originally posted by Adam Pentax forums is not the same as "nothing but Pentax" forums. If we don't keep our minds open to those users who choose to use different bodies, lenses, or systems altogether, we'd actually be doing a very big disservice to everyone involved in the community.
This is especially the case given how many other systems can use the older, MF lenses, and the fact that there are Samsung digital cameras which are Pentax clones and share compatibility with many lenses that are still currently available (e.g. the DA Limiteds).
Even the FA Limiteds and the last two FA primes (50/1.4 and 35/2) still on sale can be used in manual mode at a pinch with the aperture ring on MILC bodies (and that means Nikon too, very soon; IIRC their register distance should allow them to do this with zero-glass adapters). That's $$$ in Pentax's pocket and a rosier future for the company.