I'm really sad to see how much Watch Dogs downgraded from being such a graphically awesome game to something comparable to the graphics of GTA IV (I seem to recall they looked even better too).
UbiSoft should've allowed the game to maintain its development time for longer but nope, they see people are moaning to get the game out and so that's what they're doing it.
So.. getting this game on PS3 or PS4 makes no difference really.