A NeoGAF member going by OsirisBlack - who has been verified by site moderators as a genuine industry insider - has this to say about the rumored PS4.5/PS4K:
"Price is currently $399.99 they were discussing a better CPU which would raise the price to $499.99 we were guaranteed the price will be no higher than $499.99 (He mentioned the CPU upgrade quite a bit almost as if they haven't really decided on a final spec could be a pricing issue.) also there is currently no plan for any type of trade in program for current PS4 users but that could change.
They stated that the GPU is twice as powerful as standard PS4 and much faster. They did not say exactly how fast but that is was running at a higher clock speed while being much smaller than the original.
It will have a 4k blu ray player and will upscale games that are not natively 4k.
Also there was talk of some sort of VR lounge for the media player app which is supposed to be getting a substantial upgrade.
It was stated plainly and with no room for interpretation that there are developers that already have development kits for the PS4K and that they are making games that will directly target and take advantage of the higher specs of the PS4K. It was also stated that these games will in fact work for the PS4 but with considerable sacrifices made to performance.
It was also made very clear that current games would not be getting any type of performance upgrades by being played on the system and any benefits to older games would come via patch per game and per developer. When asked if this was going to happen the response was "Its a possibility but doubtful with the exception of a handful of games."
We were also given a list of games that will be available at launch that will directly take advantage of the PS4K where the differences are and I will quote him "Significant."
For the PSVR
For the PS4K
Deep Down (Thought this was dead)
GOW4 (This was the exact abbreviation on the sheet I can only assume its god of war 4)"
The gamers in the thread are pretty vocal about feeling betrayed that PlayStation would essentially launch a new platform with hot new games that run "with considerable sacrifices to performance" on the PS4 you bought in the past two or three years. God of War 4 being a PS4K exclusive, for example - or even GT Sport - would feel like some straight-up bullshit. I mean God of War 4 hasn't even been announced, but if I'm playing the sub-standard version on my hot new PS4? That's bullshit.
Later in the thread, OsirisBlack clarifies that the PS4K is mostly about boosting the platform's VR capabilities.
"To clear up a few things though he did not make it sound like all games would be native 4k just that they would be scaled to 4k and we do have a tentative placeholder date for late Q1 next year.And if it is, indeed, mostly about PSVR, that kind of soothes the burn - but it's not gonna' make the headset's resolution as good as the competition, either. And it's not gonna' make me feel better about what my imagination now insists is a low-res, poorly-animated version of God of War IV running at fifteen frames per second.
Tried to keep my personal thoughts out of this thread but I really believe this move is all about the PSVR trying to look a bit better when compared to its direct competition."