My prediction (taking into account what Zoetis has already said as far as assets being exactly the same and that it's just being upresd).
No visible difference in:
- Texture Quality
- Shaders
- Post Processing...etc
Unless a game is specifically made to take advantage of this new bonus power (according to the know there is such game being developed as we speak and is going to be unveiled at e3). The majority of time though the main difference will come down to upres 1080p-4k, double framerate (30-60) for all upcoming ps4 games. Would be interesting so see how much the framerate will increase in games already out running on unlocked framerates like Killzone, and Infamous. And the last solution would be (imo the best outcome) supersampling the 1080p game or using equivalent of 8xmsaa along with a post process aa solution all while running 60fps the majority of time.
Tearaway uses this solution and it is the cleanest looking game on ps4 I've played so far:
Barely any jaggies to be seen, this aa solution is what I expect at the very least for all ps4k games.