Why is everyone getting hot under the collar about a single Digic V vs a Dual Digic IV? Their proccessing through put is pretty much the same. Ie about 160 mb/s. The only thing a Digic V will offer a 5DIII is a slightly lighter chip set.
Im not sure on the 28mp / 6fps. From my math, Id make the through put at 28mp and 5.7 fps ;-)
I get the feeling that Canon used a dual Digic IV array for the 7D to bring in the processing power of the next gen camers to the XD range without having the Digic V chip ready. Which prolly means that the non 1 series XD range will. Always have dual Digic processors of the old tech from now on.
The Dual Digic V processsors are alledged to have a though put of upto 320mb/s so a 32mp / 10fps cam is quite possible. As such, I think the Digic V will be the last of its kind, Canon would not need a fast chip again, which is prolly why they are holding it back.