Right now, Canon sensors are absolutely inferior at low ISO. This is fact.
I'm not really interested in who sells the most hamburgers. If I was, I'd be shooting grizzlies with iPads and you probably wouldn't hear from me soon.
How do those touting Exmor advantages demonstrate them? They underexpose by 4-5 stops then push the shadows back up. While there are valid reasons to do that, it's an 'advantage' that's totally useless to the vast majority of dSLR buyers.
Fortunately, technological improvements aren't based on this.
The low ISO DR of the Exmor's is extremely beneficial for landscape and wildlife shooters. I know a few shooters who even tossed their GND's. Simply expose for the sky and lift your shadows later on with minimal penalty.
Michael, I think you may be missing the point of those (including me) who keep saying "but Canon sells more." I think everyone agrees that better IQ at any/all ISOs is a "good thing." That's not the point. The point is that you, Aglet and other pro-Exmor folks keep reminding us of your personal needs. That's great, and I wish you all the best in finding the gear that helps you do the job. The difficulty is that Canon will not change their technology based on your personal needs, nor based on the needs of a minority. They are not artists seeking the best quality product, they are a for-profit corporation. Canon is interested in profit, and takes a certain strategy to achieve it. The strategy, which has been quite successful relative to their competitors, is to make very reliable products and systems that appeal to a large market segment, and support that with strong marketing campaigns.
If Canon products do not satisfy your needs you should buy another brand, you can't expect Canon to deviate from a successful business practice to suit a minority need. This is not a question of art, it's a question of money. Because I accept this fact I'm not offended that Canon's sensors are inferior at low ISO (they are). I wish they were better, but my wishing makes no difference.