FPS, AF, ISO, Settings, so many of them etc, auto ISO etc, silent Shutter is amazing, Multiple exposures, just the general feel is so nice, I honestly loved the 1DS 3 before I had this in my hands, without a doubt I am so happy I made this choice its the right one, there's just so many options to this camera, its like it has everything you need, 22mps, is way enough generally, even HDR will have its uses and I hate HDR shots, but I know it could help if shooting interiors etc, its a move forward, also buffer time, its quick, the 1DS 3 is terribly slow if you turn on Iso NR, its a great camera..