yeah most games will support 120hz with a few exceptions here and there that are hard capped. Assassins Creed 4 is capped at 62fps. Very odd i think as the older games had no cap. Rage is capped at 60
Lots of games uses Unreal Engine 3, they tend to be soft capped at 62 but can easily be changed to 120 via ini file.
Mass effect 3 gets glitchy at 120, but works good at 92fps.
I've had my 27" 3d display for more then a year now, and it's really annoying when playing games with 60 fps cap now that I'm used to playing at 120fps. The difference is very noticeable when playing now.
Then you have the really bad offenders that cap at 30 >_< Star wars Force Unleashed 1 and 2 is capped at 30, but there was a community fix for that to raise it to 60 at least.
A lot of people get a bit confused about framerate and how much of it we can perceive thinking 24-30 is enough. It's enough for tv and movies as the inherent motionblur from the camera helps mask the low frame rate.
Gaming is different though where every rendered frame is perfect each and every time with no motion blur. And even if the game supports motion blur it generally isn't good enough to mask the problem. But there's more to it then that.
Your brain processes information a lot faster then 30 or 60 fps, so when you're at the point of not really seeing a fps difference (90+fps) you can still feel the difference in the controls and the responsiveness.
If you have a fast enough computer to run most games at 100fps or more, it's quite a nice experience imo.
If you can't maintain 120 FPS in a game, it's usually a better experience to just cap at 60. 120 has worked really nicely in Dishonored, BioShock Infinite, and all Valve games, though.
I'd cap at 62-65 FPS myself. If you're wanting to maintain 60 FPS as much as possible I've noticed that it's usually better to have your GPU render a few more frames than that so that if, or rather when, it drops frames for various reasons it doesn't go below 60 FPS.
Personally though, I tend to leave frame rates uncapped outside of games like Dead Space and Dead Space 2 where you have control and legitimate graphics (specifically shadows) issues with going over your monitor's refresh rate (60 Hz/FPS in my case). Too many games have a tendency to say, "Oh, you're getting 55 FPS here? Well we'll just cap you at 30 FPS!" In some ways the ones that have too much v-synch-induced overhead/trouble that results in the game running at 50-55 FPS when it would run at 90+ if uncapped are worse. Capping my frame rate at 5 FPS over my target helps out a good bit in either of those scenarios.
"Before I send them to hell, I shall let them see heaven." - Claptonvaughn, http://www.gamefaqs.com/boards/605432-path-of-exile/68145584#11