As long as you drove straight both rears would be the same, both fronts would be the same however different from the rears because the tires are different size. Obviously they would all rotate the same distance unless any were spinning.
It's too bad I hadn't added that, yes it has to be in a straight line and on pavement, no slippage. On these forums you must explain every little detail.
And NO the tires are the same size, rim size and tire width don't matter for what we are trying to explain here. My tires are 25" diameter on both ends of my Polaris 500 HO Sportsman and that measure out to 78.54" around. Each revolution the ATV will move that far ahead.
This site explains tire size better:
ATV Tire Size Explanation | eHow
This site calculates circumference:
circumference calculator
And your youtube movie reference is miss leading because it doesn't show the right front tire so we don't know how much the front differential is splitting the rotation between the left and right tires. I bet the right is spinning at times when the left looks like it's rotating slower than the rear.