CSS3: the background-rotate property (proposal)

A currently requested feature by web developers is the ability of applying rotations to background images. CSS3 specifications already allow for this kind of transformations in their transformations module, but only for page elements, not for their background image. In theory, a property that might fulfill this task could be called background-rotate. This property should accept as its value the same type of values allowed for the rotate() function used in the transformations module. A major problem that might be arise is where to place this property in the shorthand background notation. This property should look like this:

#test {
  background-image: url(foo.png);
  background-repeat: no-repeat;
  background-rotate: -10deg;
}

This image, positioned in the top left upper corner of the element, should be rotated by 10 degrees counterclockwise. Another problem for browsers is to establish an axis for the rotation. Finally, it should be carefully checked whether this transformation may actually be expensive in the context of background images.