My car gets cleaned when it rains, I live about 20 meters from the ocean, so I let the oily film remain on car, as it protects it from salt spray and rust. Water in my part of the country is far to precious to waste on cleaning a car.
I was pointing out that this oily film probably does not come from the oil spill in the gulf, but is something that can be seen on roads, in storm runoff from roads, and on cars, in any place in the world that has motor vehicles, that run on petroleum products. More cars = more oily particles in the air and on surfaces.
I hope that people will look at all the information that comes from places like youtube etc, with as much caution and skeptisim that they do with the information that comes from the mainstream media. Also use a good deal of common sense when they are dealing with any information.