Information for the EOS 5D Mark IV is coming in slowly.
We're told that the new EOS 5D Mark IV, which will be announced in August will have a new battery grip, the BG-E20. We don't know at this time if the new camera will use an LP-E6 series battery or not, though we hope it does.
There is no dedicated external wifi transmitter coming for the camera, so that seems to confirm that wifi will be built-in to the EOS 5D Mark IV.
We're also told that the EOS 5D Mark IV will see the return of the red autofocus point in AI servo mode.