I've noticed that when I set a picture from Aperture or iPhoto as my desktop image, the quality is often exceptionally bad. The pictures look pixelated or full or artifacts. I am selecting the pictures by going to the System Preferences Desk settings and choosing them from the iPhoto or Aperture lists. I would expect this if the images were too small and Leopard was expanding them to fill the screen (1680x1050) but some of these pictures are 10.2 megapixel behemoths. They look beautiful when viewed in full screen in Aperture. I've tried looking at some images centered on screen at native size, no stretching, and they still look like garbage, with all sorts of color banding and such. What gives? Just a bug that will be fixed later, hopefully?