Before 2007, Nikon didn't have FF cameras.
Even their top of the line pro model, the D2X, had a DX format sensor (1.5x crop).
So, at that time, Nikon apologists were claiming that the DX format was in fact better than FF.
One of their arguments, for example, was that FF suffers from soft corners and vignetting - and hence DX was better.
But while the apologists were arguing, pros were switching en masse to Canon.
Nikon, of course, took notice and started offering FF cameras.
Today, we have Canon apologists arguing that you don't need more DR (and resolution) than what Canon is already offering.
The situation is definitely not as bad as the DX vs FF scenario of the past but bears many similarities.
And while the Canon apologists are argueing that you don't need more DR and resolution,
my bet is that Canon is hard at work addressing these - as it will cost them dearly if they are not.
Also bear in mind that the DR debate didn't actually start whith the D800.
When the 5DII was introduced, it was very well liked and received.
Very soon, however, users started complaining about shadow noise and banding.
Thus, the so called DR debate didn't have anything to do with Nikon initially.
Instead, it was about the shadow noise and banding of the 5DII.
The D800 only added insult to injury with its high-resolution/high-DR sensor - at a time when Canon decided to reuse the same sensor, basically, in the 5DIII.
So, go ahead and brush this off as a case of 'the grass is greener on the other side' - if that suits you better.
But it's a safe bet that DR/resolution will be addressed by Canon.