I upgraded from the 7D to the 5DIII last February. I had spent most of the previous 9 months considering the upgrade to FF and comparing the D800 to the 5DIII. A switch over to Nikon wouldn't have been that big a deal as I was selling all my EFS glass. I read every article I could find, and I watched more videos than I care to remember.
At the end of the day, I concluded that the 5DIII was a better camera for my needs. I have a general understanding of the pros and cons of each system and am very happy with my choice.
I've always assumed other people made similar evaluations. But a couple of threads like this are beginning to make me think otherwise.....
Back to the topic of the thread, a potential new EOS-1 body, and potentially Canon's first foray into the "high Megapixel bodies" I wonder how high? I view high megapixel bodies as a pretty limited niche. Theoretically, it is great, but in practice, I think the market will be more of a niche. Landscape photographers, those shooting billboards, some select studio work and enthusiast that just have to have it
But if Canon is going to do it, I bet they go pretty high. I am going to guess more MP than the D800...Right now I'd guess 48 MP. That should sufficiently cement Canon as a "high megapixel" leader and provide room for a 1Dx II to come out in 2015 at ~24 MP. If true, looks like the 1D line is going to be split again.
Regarding the rumor of lenses with the release...those are something I might actually buy (I won't be buying the high megapixel body). As landscape and billboard type studio work could go hand in hand with a high MP body, I could see the long awaited 12-24 f/2.8 and 35 f/1.4 II. Lenses like that with superb optics would well compliment a high MP body.