I thought maybe a wire harness, but it isn't, the right strap is much thinner than the left, as well as the fit/shape and the fact that in this scene we know Bond is wearing his jacket. He obviously isn't carrying camera equipment on straps like some of the crew around him either.
Shoulder holster is back! I did like that for the past two films Bond's been using a waistband holster, like Bond gets later on in the novel series, but I did think Daniel Craig's 007 was missing a little iconic imagery with a shoulder strap.


