1. Carbon Fiber composition
2. Solar cells in front of hot shoe, above Canon logo for battery trickle charging
3. I chose more megapixels, existing pixel refinement also.
4. New "joystick", slightly larger, with rubberized grip surface, similar to new xbox controler, incorporating push down to click and twist left and right.
5. Realistic ergonomics, better placement of buttons rather than only thinking of PCB placement and circuit design.
6. More ergonomic mappable fingertip controls to do settings on the fly. Located on the inside front of the grip, where the fingertips are when gripping.
7. Various back lit buttons
8. Proper video autofocus, leaving primary purpose for photography but allowing usage of the video without requiring $10k of focus gearing and brackets.
9. Touch Screen
10. Built in RF flash control to eliminate needless transmitters and receivers when using Canon speedlights.

There are a lot more improvements. This is only the basic physical list.

This 5D is designed the same as cameras 50 years ago. It's made in Japan, where there is a massive 80's era Michael Jackson facility in Tokyo Disney (that almost made me vomit). There is a real disconnect between Japan and reality outside of Japan.

If Samsung, Lamborghini and Versace were running Canon, we might see some real improvements in our lifetimes. meanwhile, the Japanese salary-man works long hours designing something made with an absolute lack of forward thinking, creativity, or concern for the end user.