To add a bit of balance to the discussion.
The 1Dx has devastated Nikons Pro market sales with with autofocus issues on the Nikon D4 and D800 rife over the boards. One gent at Freds went through 4 yes 4 bodies to get a decent D800 with no AF
Combine that with the weight reductions Canon achieved in the super tele's and the amazing performance of the 1Dx in any conditions ie day/night/rain with lenses that weight 25-35% less than the opposition sorry but Canon has cornered the pro market again.
As for the new Nikon 80-400 lens is heavier,a thousand dollars more expensive and from the shots on the boards of full frame tests at 5.6 only matches or slightly improves on the 100-400 in IQ
It took Nikon 15 years to match the 100-400.
Looking at lenses Canon's 24-70 is the best on the market..the 70-200/2.8 again the best..Nikon have a new 70-200F4(complete with AF
problems) to again compete with Canon's well tried and tested stellar 70-200F4 with only the 14-24 offering something in an area Canon dont offer in the zoom dept. And a killer lens it is.
The 100-400 which to this day 15 years after release has only in the last 2 months been matched by a Nikon release its pretty clear the "lead" people speak about is where??????
Not to mention with an ancient lens mount they are unable to release modern F1.2 lenses that can compete with the Canon ones which lead the field ie the 50 and 85L's.
Having only just released a fleet of new super tele lenses at massive design expense to match Canon's and arrive some 5-7 years later than the oppositions releases there's to then have Canon upgrade all of them to weights and IQ
performance with TC
's unseen or heard of is a disaster of giant proportions to the pro sales.
If anyone is trailing it is Nikon with quality control issues, market share slipping having only just got a foot back in over the last 4 years and now the D4,D800 problem and simply being behind in glass quality for 15 years in almost every area.
Oh and if you ask i shot Nikon for over 10 years and loved my F100's but im just telling it how it is..
New doesnt mean better..in this case 4 stop VR
is the only feature that is better than a lens that has sold for 15 years is way cheaper at least as good if not better build and already taken millions of amazing images and will continue to do so.
Any wonder Canon havnt updated it, it took Nikon 15 years to match it..