First, very glad to have found this forum. I am an old timer on the hometheater forums but new to this one. I used to have a canon 70-200 f/4 (none IS), which I traded for the Canon 70-200 f/2.8 (none IS) which I currently use and have been very happy with, but it is a little heavy and I always wanted the IS feature. I bought this lens mostly to take pictures of my daughter who goes to dance competitions. there are sudden movements as you can imagine and the lighting even thought it's not dark, it's not the brightest. When I had the 70-200 4 none Is the pictures were dissapointing to say the least, the quick movement of hands and feet were all a blur. With the f/2.8 (none IS) the results are much better, which brings me to my question. Can the new canon 70/200 4L IS do a better job than the f/2.8 when it comes to fast moving hands or will it just help with the camera shake? My camera is the rebel XT.