Given the potential timing of the 6D announcement and the info that the camera may not ship 'till December, my comparison above made me realize something:
It's entirely possible that Canon's platform development has evolved to a sufficiently advanced level of rapid prototyping & production that they can almost literally tweak a bunch of sliders & check boxes like megapickles, fps, AF points, gps/wifi modules, built-in flash, etc etc that enable them to instantly figure out how much the camera will cost (one of the sliders is based on a production run of N units of course, input when the marketing department guesstimates out how many of this theoretical camera they can sell).
This enabled them to have a bunch of bits & pieces developed & in a pre-production state and wait for Nikon to announce the D600, then take the short time between the D600 announcement and the start of Potatokina to tweak the specs & price point of the 6D to beat Nikon (& to a certain degree, Sony too). The long lead-up to shipping in December is a result of this "just-in-time" product specification.
The state of DPreview's prototype camera at announcement (& the 6D under glass at the show) will be a strong indicator of how much other mfr's pre-Potatokina announcements influenced the specs & price of the 6D.