Read this article. There seems to be some confusion here over the whole frame rate thing by some & this explains why you'll want a high frame rate.

i aim for 30fps in my games, i have no trouble playing games, you will find that in a heavy firefight you dont have time to notice the difference between 30fps and 85fps, if you were sitting back and watching someone else play you would, but you are too busy trying to blow the enemy away to notice that your framerate has dropped, unless it goes below 24

"Don’t get me wrong, it is not bad to play a game at 30 fps, it is fine, but to get the illusion of reality, you really need a frame rate of 72 fps."

No doubt frames dropping into the 20's in the game is not a great idea.  That, however, is the trade-off that Raven made (I guess).  Total immersion was a big topic in the old days in Tom's Hardware forum during the Voodoo/Nvidia wars; yet 3DFX fans were more or less shooting for an average of 60fps in quake 2/UT and not bragging about ever dropping under it.

I hope that Doom 3 gives us the 72fps minimum!!  That would be a treat to behold.  You linked a great read.  We should always encourage developers to shoot for this.  For now I will enjoy SOF2 with its great AI and location damage even if it drops into the 20fps range.

thing is though, 72fps is all very good, but the illusion of reality will be ruined by the fact that you are running it at 640x480 with everything on minimum, even on a top of the range rig like dysfunctional's, you will still experience drops below 72 in games like Doom III or Unreal 2

Dark,
Let's hope that one day that will not be true... let us hope!