Would an Hourglass Traffic Light Work Better?

Mark Frauenfelder found this interesting new traffic light design by Thanva Tivawong. LED lights trickle down like sand in a virtual hourglass, letting you know when the light will change. I actually find this to be pretty confusing the more I look at it—a simple numerical countdown or a design like Damjan Stankovic's might be clearer—but Tivawong's proposal does make you think about the opportunities for improving traffic lights.