I don't think any of these charts talk about image quality as much as market penetration.
Canon had a full frame camera way before Nikon, way before anyone and if you were a professional 8 years ago, it was Canon or medium format or both.
It took Nikon forever to come out with a full frame camera and when they did, it was aimed more at the sports photographer than the general advertising market.
Consequently a lot of people have a lot of legacy Canon glass.
Also Canon jumped on the low cost video bandwagon early with the 5d2, continued on with the Canon mount on the 1dc, the c100 to 500 and most third party cameras like RED have a Canon mount solution.
Nikon is just beginning to start promoting video and now offers a "kit" with the d810, along with a marketing campaign, which in 2014 is kind of like someone at Nikon said, "you know video might be a big market", which kind of makes you wonder what they were thinking in 2009.
Once again, I'm not judging usability, color, detail, image quality, just market density and Canon had a very long head start.
In fact Nikon had a leg up in cinema and video in the adoption of their lenses. For decades the only still camera lenses used for cinema and video were basically Nikon and older Nikon lenses like the 50mm 1.2 still go for a decent price.
Why Nikon didn't capitalize on this is confusing, especially since they had no ENG camera market to protect.
So bottom line, of the image makers I know that shoot combination projects, few don't leave the door without some kind of Canon product, whether it be cameras and bodies or tilt shift lenses.
Canon covers a lot of territory and once again this isn't meant to start flaming any other brand because I own both and don't sell cameras for a living.
IMO
BC