Upload & Sell: On
dgsphoto -- Okay! Glad to know you have a genuine interest in improving your game.
I got involved with Nikon for the second time a few years ago, as I was accumulating Nikon AIS lenses for video with Canon DSLRs. It seemed obvious to buy some Nikon gear to use them on. I quit before the D800 and D600, but I don't regret not waiting around to get those cameras. I prefer the system approach, ergonomics and controls of the Canon cameras, and the IQ is still impressing me (looking forward to more improvements).
I'm glad I tried, but decided to use Canon as my main brand, and only brand for DSLR. I do have Oly for M4/3, but I'm not as serious about that smaller format. Trying to juggle multiple DSLR formats is redundant and costly -- but give it a go! Don't discuss or debate, just go buy the Nikon stuff and start doing A-B comparisons to your Canon stuff. The sooner you start, the sooner you will know if you prefer one or the other, but likely you won't keep one for certain subjects and the other for different subjects -- you'll end up grabbing one bag, not two, when you leave for an assignment or trip.