I was one of those that poo poo'd the 120 Hz craze thinking it wouldnt make that big a difference. I still to this day dont like 120 Hz TV's as it makes the movement in movies and stuff look a little too weird.
That said, I recently bought this BenQ XL2720Z 144 Hz monitor and Im here to tell ya, there will be no going back. For the first time in my gaming career, Im actually turning settings DOWN willfully in order to keep the frame rates as close to 144 as possible. I was shocked at how much of a difference it makes and how much better it makes the game play and image quality. I have a 60 Hz 1280x720 monitor that I use for all my monitoring programs and it is a total night and day difference when I move stuff even as small as the cursor over to that screen than back to my beloved BenQ.
So while Im fine with <60 Hz for TV's and movies, I dont think I could ever go back to <120 Hz for gaming and Im 43 years old with bad eyes!!