This weekend I joined an 2 days lasting workshop for motorsportphotography. The "hardware" was one of the hot topics there. The workshop was sponsored by canon and nikon. We could test some of the better lenses for sportsphotography including the camerabodys. It was very interresting.
In the Canon-Group the tutors from Canon were not really able to highlight their new !-Dx product for sportsphotography for normal users. They recommend the usage of this camera with an fix focal lenght lens without an converter/extender! They did not see a reason to extend the AF working at an max f=8 even at another coming camerabody. "Buy an better lens... If you can buy this body, buy an 4.0 L lens with 500 to 600mm..." was the answer
Almost all visitors shook their heads.
The Nikonians laughed when they heard this. Nikon was presentig themselves as a corporation that is more and more looking to become an specialist for sports- and wildlife photography.
Sorry, I didn't realise that the D3 series actual had f/8 AF sensors? If Nikon fit an f/8 capable AF system to the D4, then maybe this argument will hold water. I seem to remember that Nikon did the same sort of thing to their users when they made the D3 full frame, having claimed for years that DX was the new 35mm.
The problem with the 1DX is that Canon have not release (nor breifed their own representatives of) a definitive explanation as to why they dropped the f/8 capability. This has lead to speculation as to whether there was a geniune technical reason (i.e. a trade off), or whether it is just Canon being mean and trying to sell 1D Mk4 upgraders longer lenses. Personally, I believe it is more likely to be the former reason; the f/8 focusing capability was a great marketing feature over the Nikon pro bodies and I can't see that they'd drop it when everything else about this camera seems to be focused upon topping the D3s.