Sentiment against Canon from many of its customers comes from the fact, that Canon has been massively losing ground over the last 4 years against Nikon, Sony.
5 years ago Canon CMOS sensors ruled supreme. They got complacent, now the situation is reversed. Canon is not able to come up with fully competitive cameras - especially in the "enthusiast" user segment and especially for (stills) photographers. Too much attention seems to be going into video crap all over. Canon should make the C-line camcorders for the video crowd, and should stop bending over backwards to those cheapo-video freaks who want to use DSLRs for video ... the single most unsuited imaging gear for that purpose. These days, a proper HD full frame HD camcorder can be had for 3k ... so no need any longer to abuse DSLRs for HD video stuff.
On top of that comes Canons arrogance, its incredibly infuriating "market differentiation" by crippling not only hardware, but even firmware functions, that do not cost a thing. Combined with ludicrous price hikes all the time. 6D would have been ok as a base level "FF rebel" ... at 1 grand ... but 2 grand ... how ridiculous, when 2.800 USD will get you a Nikon D800.
Canon will pay the price very soon. They will lose market leadership for interchangeable lens cameras in 2013. Deservedly so! They really need a wake-up call. And kick out their geriatric croporate brass.
I will contribute to that wake up call. Once I "upgrade" from my current 7D to FF and need to sell my EF-S glass anyway 10-22, 17-55, 60 Macro I will also sell my EF glass 40/2.8, 50/1.4, 100/2.0, 70-200/2.8 II and take my money elsewhere, if all Canon has to offer is overpriced and underspecced cr*p.