Aside from my standpoint regarding high ISO noise (which should be pretty evident by now), I think many people will fall into the hype (which is understandable hype by those who need and use it) who don't genuinely need it.

It would be unwise for someone who is a casual shooter (whatever that may mean) or one who doesn't need to use high ISO's on a regular basis to think that buying the latest camera with the improved high ISO performance will automatically improve the image quality for what he/she is shooting (at lower ISO's). It will be an expensive lesson.

So for those who don't use high ISO's in the first place, yes I agree there would be much ado about image grain.