Canon EOS 5D Mark III sighted?

An interesting series of photos have been published on the web, showing a Japanese man testing the new Canon 200-400mm 1.4x Extender lens and the new Canon 4.0/600mm lens. The photos also show two different cameras. One of the cameras is clearly an EOS 1D series body, probably the new EOS 1D X, but the second camera is an unknown different model. It has a separate battery grip with a joystick, not known on any present Canon camera. This could well be the much rumored EOS 5D Mark III.