As of OS X Mountain Lion (10.8) one can move Preview documents to iCloud, how do I access these documents from my iPad?
You unfortunately can't, there is no related application for iOS right now. Whether this is an oversight in Preview (which shouldn't be able to save into iCloud in the first place) or a hint for things to come with iOS 6 is unclear right now.
Me Too, saved photos edited in preview and it saved them to iCloud allegedly and now i can't know where they are. Somewhere in the cloud I am guessing.