I think a bit impatient and, other than using his mirrors, I think the van did the right thing. He's reversing to the right and, in doing so, the front would have to swing out to the left. Fortunately, your awareness was high enough and the speed was low enough that no harm was done, though.
Cab said:
Oh, I hate that. I'd far rather someone actually indicates the way they're going; hazard lights seem to imply 'I'm about to do something, it might be something very stupid, but its okay, I've got my hazards on!'.
Me too on that! IMO, using hazards gives no indication of intention, they are just a warning that the driver doesn't have the wit to figure out which indicator to use.