Nikon Global has posted several video comparisons of Nikon D5 Vs. Nikon D500, D5 Vs. 1D X Mark II, D5 Vs. D4S, D5 Vs. a7SII. The Nikon D5 is already released, currently out of stock at most US store, you can pre-order & buy from Amazon | B&H | Adorama.
Nikon D5 Vs. Nikon D500 Video Comparison:
Nikon D5 Vs. Canon EOS-1D X Mark II Video Comparison:
Nikon D5 Vs. Nikon D4S Video Comparison:
Nikon D5 Vs. Sony a7SII Video Comparison: