Hmm, on Chrome 24.0.1312.69 on 64 bit Linux the depth effect is missing. When rotated, it looks like a picture of a cloud painted on an invisible wall. No problem in Firefox.
In Chrome type about:gpu in your URL bar, might give you some clues. (Then check out about:flags to see if there are any relevant options you can change).
til of about:gpu, if you haven't seen it, and you're using chrome, take a quick look. Some of the problems listed for my machine have the relevant issue number next to them. Granted some of them are behind a 403 for me, but it's still an interesting reporting page to me.
