This tells me all I need to know - they must be aiming to use the 14nm GPU designs coming late this year , I'm not so sure it will even be a 2016 product now.
If anything , Sony might try and have it read before march 31st 2017 just to hit the fiscal quarter (and I think that's their year end too). Market it as a premium product - sell it for 499.99 USD with the APU consisting of a CPU and GPU that are about 2X faster/better (by using components built at 14nm instead of 28nm)then what's in a PS4 , have 12-16 GB of ram available (2-4 used for OS, 10-12 available for games, approx. double that of ps4) 12X speed bluray drive (instead of the 6x in the ps4, 2x improvement) for much faster loading times and instead of just a standard 5400rpm 500 GB HDD, why not move up to a 64-128GB SSD (that could cache whatever game you're playing currently as well as store the OS ) coupled with a 1 TB 7200 RPM HDD , finally all PS4 peripherals would carry over with no differences save for 1 extra capability - HDMI 2.0 to allow for 4K movie watching with full range HDMI. This would be a box that could easily run any game stuck at 30 fps on the PS4 at 60 fps , or at the very least full 1080p for any game that currently lacks it while also turning up draw distance and filtering/anti-aliasing. I'm not 100% convinced such a device could be made so cheap but we're talking about something possibly not available for almost a year , if anything price might not be an issue, it might be part scarcity , with 14nm really taking off by the end of 2016, all the chips might get eaten up by PC gpus and mobile parts. Meaning there won't be a lot of PS4k available.
What it comes down to is just how cross platform support continues - if the PS4K is as it sounds - a beefier PS4 , than all ps4 software both retail / digital should just automatically carry over , if a developer wishes, patches for the PS4K version might improve performance. Ideally, no games would be PS4K exclusive , they would merely offer improved graphics and at that , possibly only for single player stuff. Multiplayer might get locked in at a specific setting to make sure no one gets an unfair advantage. Alternatively , something like a Call of Duty game might offer PS4K only rooms for maps that maybe only run on the new console but if you own the PS4 version and upgrade your console , you don't buy the game twice, it's simply better looking on the new console. I don't expect PS4 games at retail to start getting a PS4K badge, instead, a tag / by line on the box art not unlike "better with kinect, xbox live compatable, 3DTV ready" will be on there "PS4K certified".
To me, offering this thing , whenever it comes out , is merely the highest trim level available for the same car. You can buy the Mitsubishi Lancer that's a toned down rally car, or you can get the one that just LOOKS like a toned down rally car or you can get the 1 that's just a simple hatchback, they are all still lancers and look fairly similar but the guy who spend 40K instead of 20K is getting a better car.
And so, I posit , if you own a 4k tv and want a device that can support it a little better while also doubling as a 4K bluray player (if you didn't jump into that yet) , then sony bringing out a stop-gap midterm solution means that you have a reason to buy one ! Otherwise , unless you are obsessed with games looking their best but don't like PC's , you probably don't need one.