The 5D III wins on the resolution chart, yes... but what did you expect? Being a 7D owner, I more impressed by the 7D vs 1DX resolution chart because there, there is sensor resolution advantage but still the 1DX images look quite sharper.
What's also very nice IMHO is the noise chart. If one does the following, click on 5D III 12800 ISO, click on the 1DX and click on the 1D IV, there will be a little band in the middle where you can appreciate the improvement. For me, knowing that's unprocessed, it's pretty good.
I'm looking forward to having the complete review by Brian.
Cheers,
S.