Interesting it doesn't look like there is any wind involved. Looks like the truss just failed under the weight of the array. Overloaded truss? Design flaw in the shape of the structure vs rating? Old and abused truss? Fortunately it doesn't look like anyone was hurt, although it's hard to tell.
What amazes me is when the line array falls, it just sits, and leans against the truss tower. It could of easily rolled forward into the crowd, or back into monitor world.