There are rumors suggesting that Apple is set to release a refresh of the Apple iPad 3, during the October 23rd event alongside the rumored Apple iPad Mini. These rumors were sparked by a leaked list of SKU numbers for the new tablets which were expected to be revealed during the event. While half of the devices refer to the rumored iPad Mini, the others suggest a refreshed full sized iPad.
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This isn't the first time Apple has refreshed their iPad in the middle of its shelf life. The Apple iPad 2 received a processor upgrade to a 32nm A5 chip from its 45nm A5 chip.
In any case, this is just a rumor for now and we should know the facts in just a couple of days.