It appears I may have handled my keyboard case while my hands were a bit oily or lotiony, and it left prints and streaks that simply won't wipe off. I tried taking pictures, but it doesn't show up well on my crappy camera, but it looks like you would expect, only it doesn't wipe off, even with water. It makes me wonder, could they be permanently corrosive to the matte material the keyboard is made of? This is annoying me slightly, and I'm trying really hard not to pay attention to it.