I think I believe it.
Sony hinted at it around October last year, Shuhei Yoshida mentioned the possibility of a 4K PS4 in the future, while talking about various PS4 related topics such as PSN name changes and clarifying that PS4 won't be backwards compatible with PS3 games. Of course this wasn't announced as something they were working on but he did seem quite open to the idea and stated it would be easy to do with their x86 architecture.
He may even have talked about it before then and although I don't know how they'll manage to sell two near identical systems, I realize that it could put them on par with whatever the NX is going to be and bridge the gap slightly between PS VR and PC VR. I wouldn't be surprised if this was considered as a possibility much earlier in the development of the PS4 and I would guess Microsoft had considered a similar strategy.
It has slightly put me off buying a PS4 for now though, I was planning to get one within the next few months but I might hold off a little longer now.












