Canon is one of the relatively few manufacturers that develops its own sensors. This means that they're in a great position to create new sensors with new capabilities, and that's just what they've done with their new 35mm Full Frame CMOS sensor for video capture
Why would you use CCD when CMOS is newer and cheaper?
Recently I've been expressing the view that all cameras are pretty much the same, because they all use the similar technology (give or take) for their sensors. I don't mean to be unnecessarily cruel about the work of camera manufacturers – taking an electronic component such as an imaging sensor and making it into a usable tool is far from trivial. Still, the absolute performance of cameras is determined by what you can get off the lump of silicon behind the lens
Somehow, I managed to overlook the fact that last month saw the death of Bryce E. Bayer, the man who decided that the best way to make a single-chip colour imaging sensor was to silk-screen a pattern of coloured filters on the front