Displaying icon image for WordPress post formats, is there a cleaner way to do this?

Using CSS and image sprites is exactly what I do in Oenology. (See it in action here.)

Mine is a bit tricky, because I change the post container based on post-format type (some have post headers/titles, others don’t; some have left/right margins added; etc. – also, I have dark and light icon sets, based on the color scheme selected). But, here’s my code for dynamically generating the CSS (lines 418-598).