Some interesting observations about the latest fad in photography, the image stabilization system lens.
My experience is that activation of the system actually degrades the quality of the photo.
Unless you are partially activating the focus / exposure button, thereby activating the ultrasonic or gyroscopic system to allow it to come to full speed before actually taking the photo, the system is actually introducing all kinds of vibration your camera is not seeing without the system switched on.
How many people sit there with their finger on the clicker waiting for the system to come to full power before taking the photo? If it takes up to a second to become stable, how can it have worked on an image that took only 1/250th or 1/30th of a second to shoot?
Action is usually quick, and one triggers the camera several times a second in the case of a wild animal, bird in flight, sports, or young children. One is much better of setting the aperture to the lowest (wide open) setting and making sure you are focused on the eye to get it sharp, and click away.
Could this be why some of the older lenses are actually producing the sharpest images?