The Lead Architect of the PS4 Mark Cerny was in an interview with IGN, where he discussed how the console was specifically made to be easy to develop for and some cool new features.
Cerny describes how the PS4 will be ready for the future and claims that the full power of the next-gen console will increase as the years go by. He explains what will happen when the PS4 launches as well as what will occur several years down the road.
The interview did get technical, though, so we've devised a list on what was discussed:
At the beginning of the PS4 cycle, most games will not unlock the PS4′s full potential.
Earlier PS4 Games will use "straight forward" features of the console, like its visual power and bandwidth.
Later on, the GPU will be used for many other objectives besides processing graphics
The GPU can do things like "physics, simulation, collision detecting or ray casting for audio or the like."
The extra stuff will not make the visuals worse.
"Some of these phases [within a frame of animation on-screen] don't really use all of the various modules within the GPU."
When there is free space on the GPU modules, it will have room for other tasks.
It will "improve the quality of your world's simulation without decreasing the quality of your graphics."