I just watched "Time: Daytime", part 1 of the BBC series "Time", presented by the awesome Michio Kaku, a physicist. A very interesting search into time, with some very exciting and interesting discoveries. Being a IT guy, one thing struck me in particular: The test in which time seems to slow when you're in a life-threatening situation. For me, this explains way better why gamers want the highest fps possible.
The test, in which a guy falls from a 12-story construction, shows that adrenaline (or another hormone that influences us when we're stressed) actually has an effect on how we perceive time. Even better, adrenaline seems not only to increase our heart rate and breathing, it also increases the speed in which our brain processes signals! The test included a high framerate LED display which was showing a number and it's negative in a very high oscillation. So high that normally, the guy the test was conducted on, couldn't read it. When he was falling down with the display attached to his arm, he could actually read the number (or at least close enough to indicate his brain sped up).
There we have our conclusion to why framerate matters for gamers. Actually, the question always intrigued me, since we know form television and movies that anything above a framerate of 24fps is not detected. Although there are some other reasons why a high framerate matters, I think this test actually showed us one of the most important reasons. Gamers tend to be high on adrenaline, after all!