I don't think that the problem is figuring out Windows 8 (something that anyone could do given enough time), but, rather, the real problem is unwillingness to buy. Having heard from friends and the media that Windows 8 is radically different, any remaining interest is dissipated on sight of screenshots or a demo computer in-store.

That said, my parents, when actually confronted with it, were fine; they weren't huge fans, but using the new interface wasn't a problem after they adjusted.