Maybe Canon does know what they are doing.
Being number one keeps Canon number one due to customer marketing and sheer brute sales force. If more people would shoot Pentex or even Nikon, more people seeing this might wonder "Maybe that's a good camera, too"?
But as it is, around here (northeast Germany) Canon nearly seems to be a monopoly manufacturer, I was on a general club meeting (sports, animal protection, carnival, you name it) this weekend and 99% were using Canon, from Rebel to 1d - and one Nikon. Only people who are more into photography like wildlife photogs seem to even consider another brand.