i have owned three 1D mkll's and tend to put lots of miles on them. some go into underwater housings, some go to some some nasty environments, and one is almost welded on a 400 2.8. as a tool to deliver publish-quality shots, these do the job day in and day out. the battery life is good, color's vivid, etc, etc. so if you need a camera that you can use day in any kind of weather that your own body can endure, this is the camera for you. the file size is fine for 99 % of the magazines out there.
what could the improve on the next model: 1) newer battery technology--nikon has them here. this would lead to a slighly lighter camera; 2) improved autofocus. big debate on this with the camera, but mostly from people using them for fast sports magazine work; 3) i would like multiple "manual" settings levels. this would provide for swinging in and out of stadium shadow light. i'm not a fan of AV/TV and prefer to control my settings, but during late afternoon this is a challenge; 4) improved flash performance; 5) even with the new screen you still can't really tell if a shot is in focus! what's with this? there needs to be a better way of measuring in focus shots.