Canon has announced it will be releasing a firmware update for the EOS 5D Mark III that will provide uncompressed HDMI output for videographers. It will also enable autofocus using lens / teleconverter combinations with an effective aperture of f/8, using the camera’s central cross-type AF points in a similar fashion to the recently-released EOS-1D X Firmware 1.1.1. However EOS 5D Mark III owners will have to wait until April 2013 before the new firmware becomes available.
News: Digital Photography Review (dpreview.com)