They did? In 2008, Canon and Nikon were nearly neck and neck in dSLR market share at 38 and 37%, respectively, but by 2010, Canon rose to 44.5% while Nikon fell to under 30%. Who's bleeding share, here?
I'm not saying the trend will continue, but historically, your statement is just plain wrong. Canon can look at the above numbers and come away thinking they don't have to change a thing...
One other key point - we're talking about FF cameras costing in excess of US$2,000. That's not the real competitive battleground. Sure, it's interesting to us here on CR...but the overwhelming majority of dSLR purchases are entry-level bodies with kit lenses, and that arena is the real driver of the overall sales figures. Granted, there's a trickle-down effect, and when pros are seen using Canon or Nikon that impacts consumer decisions to some degree.
Yeah, that's your favourite statistic, but Nikon have been on the move in the mid-ground for a while now and that is where there are high margins and volume, for both bodies and lenses. Granted, there's quite a bit of lag in the system because the "advanced amateur/pro-sumer" or whatever name you wish to give them, tends to own a good collection of lenses. With growth in the DSLR sector now basically static, Canon would be fools to ignore this segment. My view is that if Canon continues to signal that they intend to play second fiddle to Nikon, more and more people will consider the switch; I cannot be the only person that does the 'back of cigarette packet' calculations of trade-in costs every time I hear rumours like this...
A 5DIII with weak AF stacked up against a D800 with more MP and better AF will not cut Canon as deeply as it might appear. People with a 5DII and a bunch of L-series lenses, people with a 60D and a couple of EF lenses, those folks are unlikely to sell it all and jump over to Nikon in droves. The number of first-time purchasers with no system buy-in and no brand loyalty who jump straight into a >$2K FF camera is vanishingly small, especially relative to the number of xxxD buyers.
We're not all going to change systems every generation based upon who's got the 'best' specifications, but when you see your chosen manufacturer continue to underspecify versus the competition year upon year and when you know that they have access to the same sort of technology, you start to think that they're taking you for a fool.
This sounds like an anti-Canon tirade, which would be unfair based solely upon a rumour. Let me just state that I'm not buying any camera equipment until all the major players show their hands this year and then I will be making a long term decision on whether to stick or switch. I'm pretty sure that I won't be the only person in this position.