Initially, the PC makers are going to be left flat-footed, which will mean rather more mini Macs sales than otherwise, but I think this is going to give a big push to not only HTPCs, but (comparatively) little PC boxes, too.
All different kinds of little boxes. Eventually, as they come online, the mini Mac will fade, for just that reason. Since the PC world isn't a top-to-bottom monopoly like the Mac world, we'll eventually see all different kinds of little boxes meeting all kinds of needs: smaller small boxes for those with small needs, bigger small boxes for those with bigger needs, and most will be a lot more configurable than Apple's.
That's the killer advantage the PC world will always have over the Mac world: diversity and flexibility.
So the real question isn't how many mini Macs will get sold, but whether small PCs will become mainstream sooner rather than later.
