I agree with both nuffi and jdizzle on their last posts.
There aren't enough change from the Mark II to the Mark III for me to feel like I'm getting any value.
I'm probably one of the easiest consumers to prey on too. I bought 5 600EXs just for the RF. So if Canon can't convince me to upgrade from a Mark II to a Mark III, I have to think there are others who feel the same.