I have been to a playa, (the Burning man Playa, not the one in the picture)and I know firsthand how hard the wind blows out there. The playa is basically four hundred miles of dried prehistoric fish-shyt. Its very fine and soft, but it is a sun-baked crust, which means it could be a hoax. One could drag the rocks, and not leave footprints. That seems more likely than the wind blowing them. I think if the wind did manage to blow them, it would be on top of the crust, rather than leaving a trail, as though they were dragged. Who knows, though. Maybe they do move, somehow. WTF do we know?
edit:
Now that I've read a little more of the wiki page, I can sort of see how its possible. If the ground is very smooth, and if it is wet, and frozen, and 90MPH winds hit the ground, and concentrate the force of the wind on the first few inches above the ground, like a hovercraft almost, the rocks can almost slide like an airhockey table.
Someone should call mythbusters.
