There is a very visible difference between 47 and 60. Try it with FRAPS, lock your framerate at 47 and see the dodgy framerate when you turn, then compare it to 60 if you feel like proving it.
60 and 120... If you're looking for it, then you're going to probably notice it. Whether it improves your gameplay/reaction etc is negligible IMO. It's nice to have though.