Well, I think this will be partly solved when the rest of Poser is rewritten to be capable of using more than one core (most people nowadays have at least 2 cores).
So I think (hope) it's kind of scheduled to be done, eventually (P9?).

A complete rework (to meet 21th century programming standards) of the Poser app is urgently needed, I reckon. Ideally, the posing part (including loading stuff) should be as fast and painless as working with any high-end 3D modeling package, since Poser is no you-get-what-you-pay-for freebie.