Did you see this part of the PW article about RK Rowling's decision to use her eBook options to self pub Harry Potter material:
"...many people who work in publishing think that as interesting as Pottermore is, the endeavor says less about the future of book publishing than it does about the singular status of a very wealthy author who has the inclination and means to build her own brand."
You're kidding, right?
This is certainly a game changer. From what i read she owns her ebook rights, so her publisher is getting nothing from this.
That's the big difference between her and Patterson, King, etc. is that she owns the ebook rights while these other authors don't. But could easily for future books, and even if they don't to build their own storefronts, I could see authors of their sales status forming a consortium so they don't have to take the burden on themselves.
So yes, this is definitely a game changer.