These are two great brands of camera for photography but from my observation Nikon camera seems to have an edge over Canon's because of some features it has.
Nikon has a EOS Mount system which canon doesn't have,this helps one to use the manual focus lenses the way it should be I.e at full capacity.
Nikon camera fits the hands better and the control of it is maintained, its usability is very high, the picture quality looks more real and natural as in it gives one the opportunity of capturing images in the raw form, no pops or some touch up images
Nikon makes cameras that can really be used by photographers that knows what they really wants.
The flash on Nikon outdo the one on Canon and it helps to simplified usage and the constant use.Nikon gives cool tones.