I just installed this little gem to my newly-Tiger-ified iMac and it works like a charm. Letting Mac OS automatically change my desktop images is nice, but it's no substitute for having an ever-editable/resizable/freely-arrangable selection of my favorite pictures as the desktop.

I also use this for the more "serious" task of putting reference images relating to my current project on the desktop, so they're always available via Expose's F11 hotkey. Quite handy.