That's the same video as before.
Question about silent shooting mode: is the shutter release slower in silent shooting, or is it the same speed? Notice any difference in the delay?
Oops, I updated the video link.
Yes, the shutter is slower (3fps max) in silent shooting mode. (expand the shutter section at http://cpn.canon-europe.com/content/education/technical/inside_canon_eos_5d_mark_iii.do for more info)
Once its focused, Canon specs it at 59 milli-seconds, faster by a bit than the MK II. Its a larger mirror than the 7D, so it takes more power to move it, and it doesn't have a high voltage battery like the 1 series. Thats 0.059 seconds, pretty fast, but not instant. it is the same as the 40D, 50D, 60D, and 7D.
"Shutter and mirror The 5D Mark III shutter has a 150,000-cycle durability rating, the same as the 5D Mark II, but the shutter lag has been shortened, to 59ms in the new model from 75ms in the old .
The x-sync shutter speed, at 1/200, is the same as before. With Canon Speedlites, High Speed Sync above 1/200 is possible as well.
The mirror mechanism has been reworked to accommodate the camera's faster frame rate. The main difference is better stability - less bounce - when the mechanism is in the down position.
The improvements to the mirror, says Chuck Westfall, Technical Information Advisor at Canon USA, pave the way for two new quiet shooting modes. Called Silent Single and Silent Continuous, they reduce the amount of mechanical noise emanating from the camera in both single-shot and continuous shooting (the latter is restricted to 3fps when operating silently)."