Funny you should mention the 24-70L II, I just read through the 1D-X "AF Setting Guidebook" published in June, and it says on pg. 37 that the 24-70L II is scheduled for sales start in July 2012
Oh, and the old 24-70L is not a group A lens like the Mk II, but only a Group B lens so you loose 4 diagonal-cross sensor points (the off-center AF point ones).