If I shoot things moving in a steady pace and in pretty much one direction, like a runner or a car I keep it on, always. If I shoot hockey or kids or soccer I shoot with only vertical IS on (or off if I'm in portrait mode), that way I can snap the camera back and forth and not see that slight drag/delay in the VF but still have the benefit of some stabilising, absolutely helps predictive AF.
So it's not about shutter speed for me, but how the subject moves.
And as mentioned above here, 1/200s at 200mm rule doesn't work all that well with high mp bodies. I will always use 1600 or 12800 ISO to get fast speed rather than one step cleaner image with slight blur.