They are so close that it always comes down to aesthetics and minor differences:
big sell for me has always been so petty:
Deleting an image on a canon takes 3 pushes of 3 different buttons but nikon is double click of a single button.
Canon's dials are backwards (I know, i can change them)
GUI in Nikons look better to me
They have a cooler strap.
Once you have a camera, check out my site, you'll be up and running within an hour