
I seen a diagram of how the IS works, cant remember the site now.
but basically when its on the is a free moving lens in the middle the counters and movement in horizontal and vertical planes. This re directs the light back to its 'normal' point
you can test by aiming at an object IS on, half pressing the shutter and move the camera up and down a little etc and you will notice the image will remain fairly in the middle, with IS off and do the same the lens markers will just move around the object....its pretty cool
another lump of pointless info lol