We got this from Fred Miranda, which is a forum I frequently read.
For me, the obvious feature of the 1DX Mk2 is its AF and tracking capabilities over the 1DX. Not only is the AF faster, when using a 2X TC on a 500/600mm f4 lens, the new camera will allow all focusing points to be active even when the effective aperture is f8. On the 1DX, only the centre AF point and 4 surrounding points (with AF area expansion) are effective. I understand there will also be a multi-frame silent shooting mode instead of the single shooting silent mode on the 1DX.
If we go by other things we’ve been told about the EOS-1D X Mark II, there are some similarities, though the exact information may not match up perfectly.
More to come…