Stephen Oachs of ApertureAcademy.com posted some photos of the new Canon EF 200-400mm f/4L IS USM Ext 1.4x Lens being used in Kenya.
Mounted to the 200-400 was an unrecognized Canon DSLR. The Canon EF 600mm f/4.0 L IS II USM Lens was reportedly being used by the same individual.
Check out Stephen's story and pictures.