I have a unibody MacBook with a native resolution of 1280x800. I downloaded several wallpapers from interfacelift.com all at 1280x800 and whenever I use them as wallpapers they appear either scaled up and pixelated or severely scaled down (at "Fit to screen" and "Center" respectively). Previously I had a 17" PowerBook at 1440x900 and didn't have that issue. I've imported the images into Aperture and according to the metadata they are in fact the 1280x800 versions, so why aren't they displaying properly when applied as desktop backgrounds?