I feel sorry for Nikon owners.
It doesn't matter what model they buy, even when first released, as a few months down the track, Nikon will bring out a new and improved version of it making your current model obsolete and now worth substantially less than it cost you. Remember the D600 then the 610?
Canon does hang onto models much longer, and hence they have better re-sale value later on as say, after 3 years, your Canon may be just superseded, but if you had an equivalent Nikon, it would be 3 models old and practically worthless.
I'm not saying that Nikon cameras are no good, in fact, they are very good indeed, but constant model updates is not how you keep up the perceived and resale value of products.
It also makes it more difficult regarding spare parts too, as many models mean lots of parts and distributors only have so much space and money for parts.