I've been thinking on this for a while and I admit the idea's still
only half-baked. But I thought I'd toss it out to the list for
commentary.
I think there are three kinds of design for product features (web site
features also, not so much with intranet features).
1. Core design. This is "the good stuff" that we all want to be
doing, that we have tools and techniques aimed to support (personas,
contextual design, et cetera).