It looks like the Canon 5D Mark 3 might finally have been spotted out being put through its paces on a shoot. Blog "Aperture Academy" has images of an unidentified Canon camera being used with two new lenses.
There are two camera bodies in their images, one looks like it could be the 1DX as it has an integrated battery grip and second display. The other has a separate battery grip which may be the Canon 5DIII or could be a Canon 7D replacement although the 5D3 looks more likely as the camera body pictured doesn't have a built in flash.
http://blog.apertureacademy.com/2012/01/canon-200-400mm-and-600mm-prototype.html
