I probably should have posted in the first couple of pages, before the thread went off the rails, but.
I Photograph Wildlife mainly, Long Lenses mostly, either in Africa (Dusty/Muddy at times) or in the Arctic/Antarctica (Cold/Snow/Water/Ice), I've used most of Canon's non Pro bodies in an attempt to keep weight down, and a few of Nikons as well, in the types of Photography I enjoy most the pro Bodies, Canon & or Nikon, simply do the job better and with the most reliability, and when your + 1,000 Klms from the nearest Canon/Nikon store, it's mostly about reliability.
The weather/Dust proofing you get on a 1Dx is about as good as you will get today short of an Underwater Housing, the Burst rate @ 12 fps is exactly what you need to freeze a Cheater in flight at 100kph, the ruggedness and drop ability (new word ??) of the pro Bodies is again what you need in a harsh environment, this is a package developed for People that want to get the very best from the equipment in generally harsh environments, it has the ability as well of being just at home at the Local High School Sports meet.
the fact that the Bodies are large is only a concern in the carrying of the said Camera & attachments, if you could get all that the 1Dx is, into the body of the 5DMK III, I'm on the list of buyers, but until that time arrives, I'll continue to use & enjoy the results of the 1Dx, until of course the 1Dx II arrives.
I'm off to Europe over Xmas & New Year with the Family, the 1Dx stays home & the 5DsR + 5D MK III go in the Bag, unless I find out there's an Elephant in St Marks Square, or the Lions are back in the Colosseum, or the Huns are back in Vienna for the Xmas Season.