while people are pointing out that "why would he openly wear the strap of an unannounced camera", note that he is wearing the strap "upside down", with the lettering turned in. it is only because it is half twisted in this side on view that we can see it.
i.e the strap is being very deliberately worn in a non-traditional manner.
I guess the question is why would Canon make a custom strap for a camera that is not available in the market?
1DX, 5D3, 600D, RX100
16-35L, 24-70L II, 70-200L II, 100-400L II, 50L, 85L II, 135L, 17TSE, 24TSE, 40, 100 macro, 18-55 II, 55-250 II, 1.4x III, 2x III, 600RT x 4
When it comes to gear, it is better to vote with your wallet. Bitching on online forums like a lunatic doesn't get you anywhere!