I'm not sure about this but the 24 fps eye limit thing may be misleading. Even being true, it doesn't mean that you won't notice the difference when video goes above 24 fps, due to synchronization issues I suspect. The game's fps may not be synchronized with the brain's image processing.

Note - the above is just a guess, I'm not an expert in such stuff and I'm not in the mood to research it right now :)

24fps is the very minimum where things will appear to be in motion, any lower and its kinda jerky and appears to be a series of individual still frames. The reason movies are 24fps is because they didnt necissarily care about having really smooth motion, just doing what they needed to make things appear in motion.

Another thing to remember is that film has motion blur, which helps to make 24fps look smoother. Motion blur is something that some newer games have, and it does help 30fps games look smoother. Still, 60fps is preferrable.

What's motion blur?

Does crysis have it, casue when you have the shard quality on either medium or high, the screen sort of "blurs" when you turn really fast, and i love that effect.