Neuro, it took me a while to figure out your point of contention. I have always understood that "separate AF processor" to be the second Digic 4. This view was reinforced by the fact that the 1D-X has dual Digic 5+ processors plus "An all-new, 61-Point High-Density Reticular AF and 100,000-pixel RGB Metering Sensor that uses a dedicated DIGIC 4 Image Processor". With respect to the 7D, that dedicated AF processor is never named, so it seemed logical that it was the second Digic 4.http://www.usa.canon.com/cusa/consumer/products/cameras/slr_cameras/eos_1d_x
But, I stand corrected. It does appear that the 7D has a third processor (in addition to the two Digic 4's) dedicated to auto-focus. (I now understand it has a fourth for A/D conversion.)
It's curious that the 1D-X uses two Digic 5+ and one Digic 4 to achieve it's phenomenal performance. It's also curious that the 5DIII has a single Digic 5+. I can't find documentation suggesting an additional processor in the 5DIII dedicated to focus. Given that the 5DIII doesn't offer the burst capability of the 7D and, according some users on this forum, the 5DIII also doesn't match the 7D for sports shooting*, it would seem that a single Digic 5+ won't be enough for the 7DII to top the 7D in IQ, burst mode, and focus tracking. Hence, my guess is that two processors will be needed. Maybe not dual Digic 5+, maybe a single Digic 5+ and the same, unnamed processor that the 7D uses for focusing. Or, maybe a Digic 5+ and a Digic 4 for focusing like with the 1D-X.
Hey, if Canon can improve on the 7D in all areas with a single powerhouse chip, then I'm wrong. But, I don't expect them to do so. My guess is that Canon will continue to dedicate a chip (maybe not a Digic) to focusing. Parallel processing is easier with multiple chips.
*I understand "sports shooting" to mean focus tracking, since this is often more valuable than burst mode. But, I concede, that "complaints" about the 5DIII for sports could be limited to its slower FPS.