I'd go canon, i do professional wedding photography and videography and i can honestly say i see NOBODY using nikons, for anything...
First things first, canon beats nikon for video, anyday all day. Theyve been doing it for longer. The canon 5d mark ii shot the short film "hell and back again" and was nominated for an oscar! Thats amazing considering its a 2200 dslr camera.
in terms of photography i honestly think its personal preference.
I have a 5d mark iii and a nikon d7000 and i like the colors in the canon but i think the d7000 is faster.
the one benefit of canon is the lens's are cheaper
the nikon 24-70mm f2.8 is 1900, the canon 24-70mm f2.8 is 1300
Both are fantastic cameras and you wont go wrong with either or, but canon is taking over...
Canon 5d mark iii owner, nikon d7000 owner and Pro wedding photo/video