When I visit Nikon forums a find a similar mix of high praise, complaining and disappointment.
During pre Internet days we were never exposed to such a flood of wide-ranging reaction, and I do believe most forums of any kind, by nature, attract more complaining.
I don't remember, did Canon promise two, three, four more stops of speed from the new body ? That wasn't the most significant improvement I was expecting.
During my long career none of my pro cameras have ever been perfect. Many great features, a few that puzzled me and some things I was always left wishing for. The steady improvement though has had a real impact on my work. For example, look at the improvement in sports photography, wedding pictures, digital photography in National Geographic, and If you can, visit the White House to see their historic collection of images. The recent ones are extraordinary by comparison. Large, sharp, beautiful, noise-free images in very low light of our dark-skinned President.
Canon USA and CPS welcome comments and concerns, and they share them with the people in Japan who make the products.