At least we aren't talking about RAW video!
Codec talk has been running rampant for a while in regards to the 5D Mark III, is most of it fact or wishlist?
According to EOSHD, Canon is working on an MPEG2 based codec for the 5D Mark III. It will have a 4-2-2 color space. Another feature will be a variable bitrate up to 50mbit. The codec will be an improved version from the XF305
The move is motivated by the desire to avoid paying Sony and Panasonic a licensing fee for AVCHD/H.246.
Adobe and Apple have already taken up the format, so applications for native editing will not be a problem.