Wouldn't the push for PC 4k standardization have a somewhat negative impact for the next few years, until GPU's are massively more powerful than today's best? Also, even as these cards are notably increasing in power with every new model, RAM speed and memory bandwidth aren't necessarily advancing at the same pace. That'll be a real issue that may take quite a while to solve if targeting 4k.
It's like everything top developers & middleware vendors were just recently boasting about - with their new engines and stuff - will be pretty much impossible at those crazy resolutions, while still maintaining the performance and features/FX that they were planning to wow everyone with.
Things were just now starting to get very exciting in the world of GPU performance and where graphics are going. I don't see many developers trading in all that just for a resolution bump.
Then there's the practical side to it all. While there's no argument that 4k on PC will allow more vivid IQ, it's just not going to be as noticeable as on very large screen TVs, which currently have worst dpi than PC screens. Given all that, it's asking developers to displace a heck of a lot of GPU power, for such little gain.
I think 4k PC standard(for everything besides games) could be another 2 years away. For games, however, I don't even want to imagine when.