SBIcon is a class representing an icon displayed by SpringBoard. It is not typically used directly; instead, its various subclasses are used: SBApplicationIcon, SBBookmarkIcon, SBDownloadingIcon, and SBDestinationHole (which is a blank space used when rearranging icons).
In iOS 5 Apple split up SBIcon, creating a separate class for SBIconView, and just leaving SBIcon with behind the scenes stuff.
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