::Sorry, I guess I was kind of being a genre warrior up there:) Anyway, I've given up fighting for alt-rock since it seems to be more of a collection of genres than a genre itself. However, going solely by Wikipedia itself, it seems to be that the only real difference between pure grunge and post-grunge is, as I said above, post-grunge is more radio-friendly. I won't go to war over it or anything, but I think post-grunge is close enough to real grunge to be considered punk.