If there are going to be gradients, it would be nice to be able to link to SVG gradients, i.e.
background-image: url(svgfile.svg#gradient_in_defs);
then background-repeat, -clip, -position, etc. can be used to manipulate the gradient as if it were a regular background image (but of course, scalable). Use of SVG patterns would be nice, too. (But is all this already included with using SVG images as background images? Can an SVG document’s components be referenced with a hash, etc?)
Someone above suggested clipping with EPS outlines. I suggest that using SVG clipping paths (or masks, for really impressive effects) might be better, as browsers are already beginning to support SVG. (Opera has SVG Tiny support, Firefox trunks have partial SVG support, and Safari/WebKit is working on it.)
Some people above have suggested that the syntax for multiple background images should be:
background: _background 1_ ;
background: _background 2_ ;
That doesn’t make sense, as it conflicts with the CSS inheritance model. (How would you override it? Wouldn’t you just add another image?)