Mmmmh.
You see, I never had a problem with the concept itself of PS4K since, well, I'm one of those people in the camp that believes in the family of consoles as Nintendo's next evolution hardware-wise, with a quicker hardware refresh rate and consoles and handhelds sharing games. Also, DSi and New 3DS are, indeed, revised versions of already existing consoles which are quite more powerful than the original in several ways. So yes, it's not like I refuse the concept of generations becoming more fluid, with mid-gen refreshes.
But, if the infos shared by OsirisBlack are true, I'm not that positive about Sony's execution, mainly for two reasons
1) I think three years is a bit sooner for a home console powered-up restyle. IMHO, 4 years between the original home console and the restyle would make this practice more acceptable, since 4 years is nearer to what people can expect as a decent "generation" length. Also, I think that people are much more used to buy mobile / handheld devices restyles than home devices assuming a 3-years time period between original and new version, due to how much they use them outside their houses and thanks to different payment methods for mobile devices. But, to be honest, this is more of a personal feeling, maybe people (by "people", I mean general audience as a whole, not just enthusiasts) is ready to buy home device in PS4K's price range at this kind of refresh rate. I doubt it, but it's possible. Especially if it's $399.99
2) This is my main concern about what stated in the OP: how it says that not only developers have PS4K dev kits already, but the development is going so much towards PS4K that upcoming PS4 games will run on regular PS4s with "significant sacrifices". It's how it's worded that worries me the most. I was expecting a smaller increase in specs, honestly, this seems quite more than what I thought, considering the starting point, but that's besides the real concern. You see, there are exclusive games on DSi and New 3DS, but they didn't / do represent the majority of DS / 3DS lineup, not at all. Most of all, though, there aren't games that are so much better on the restyles, that the development of which was so focused on the new versions that the original hardwares got a shitty treatment. Aside from Hyrule Warriors Legends, which is a game that clearly saw a development focus on New 3DS, seeing how badly it performs on the original. And that's my biggest worry with PS4K IF (a gigantic, massive IF) games really take so much advantage of the new hardware that original PS4 owners can still enjoy those games, but with "significant sacrifices": that those "significant sacrifices" result in Hyrule Warriors Legends-like scenarios being more spread and right from the get go. That would mean pissing off the 40+ millions of PS4 owners when this revision will come out, if it's that spread, and that could be quite difficult to face, both comunication and marketing-wise. Depending on how significant the sacrifices are, that would fragment the PS4 ecosystem, which seems to me like the exact opposite of what Sony should try to achieve with this kind of move, in the same way (to make an example) DSi and New 3DS represented by far extension of the ecosystem, not fragmentation. Even if New 3DS' announcement declaration were kind of pointing to a situation more similar to PS4K (exclusives), despite the lack of statements about games on older versions getting the short stick.
We'll have to see if this rumour is true and how the real thing is executed of course, but this supposed course of the events doesn't sound as positive as I thought at first. Or better, much less consumer-friendly than I thought given the circumstances.