They won't do that because of the profit and competition. It's not like any othwr developers are stepping up to compete. In a way they're pushing each other to be better. If they team up and make a baby they're gonna get lazy and divorced. Just a thought.
I have both a PS3 and PS4. I like how more reliable the PS3 is over the 360 in terms of playability. My PS3 is 4 years old and is still trucking while my cousin has gone through 3 360's because of RRoD. As for the PS4, I've tried out an early edition of the Xbox One, and found the Kinect to be horribly unreliable and the controller to be clunky. And from that I decided to get a PS4. But with what Microsoft is doing with the Xbox One now I may get a one just to experience the exclusives. Both companies consoles (PS3, PS4 and 360, One) are great consoles in their own right, but for the most part it depends in what your play style is.