I have a similar issue of jittery images Firefox only (Chrome and IE seem to be fine), when scaling images: http://holiday.cmog.org
I've added hardware acceleration to the body with translate3d. I saw the comment about adding 0.01 deg rotation --I can't add that in a tween, as it overwrites other transforms I'm using to center the images (translate X and Y), but I've added it the style of the images. But those don't seem to be doing the trick.
Any suggestions?