The tests were done with footage of real life shot and displayed at varying frame rates. Google Douglas Trumbull. I'm having difficulty in finding specific data on this test but the point is number of light particles or whatever is irrelevant. It only matters what people can perceive.

: Especially in a world without perfect motion blur, 72fps is easily
: discernable from 120fps. And depending on what you're doing (i.e. moving
: your mouse on your desktop), I'd bet 120 could be discerned from 240 and
: maybe even higher.

Depends if you've got a screen that can actually natively display those frame rates, for starters. And personal anecdotes don't hold much sway, anyway.

Trumbull's new format is going to shoot in 120fps though, not only for higher emotional response in the desired format of delivery, but also for easy and direct compatibility with various formats tv/cinema formats and the ability to show certain scenes (like action) in higher framerates while still achieving the 'look' of 24fps cinema overall.

I find it kinda fascinating really.