120hz was made with 3D in mind more then anything becaue when in 3D mode you hz is cut in 1/2 so a 60hz would go down to 30. A 120hz is operating at 60 in 3D mode. Other then that they have a little advantage when displaying fast motion. LCD displays do not flicker at 60 hz like CRT displays did so there is likely no real improvement.
Well I think I can see some small changes when I play, in cleanness or are im crazy?
During fast motion it might appear clearer. I would think that you would notice more of differance with an FPS game with lots of very fast action. They now have 240Hz models. From what I read they clear up the back ground to the point that the blur does not work for fast action anymore and you can actually tell the background is fake so it does make some differance.
So, like, I max every setting on this game and I run it at 51 Hz. The reason why? My HoN looks smoother. Because I can enhance the anti-aliasing by 16x in any application that uses it. Let's see fancy Windows 7 do that!