Here’s a couple of humorous videos from a series called Weapons of Mass Production (WOMP). These guys go to great lengths to compare these cameras, both outdoors and in the studio, even bringing in “a couple of ridiculously hot models, with barely any clothes on and…a robot.”
The next video is the Canon EOS 5D Mark III and the Nikon D800 reviewed and compared. I particularly like the sledgehammer test, although notice that they only put the Canon to the hammer (the Nikon is owned by the reviewer). 🙂