According to sources, who were unable to see the keyboard themselves but heard about its existence from those who had, a small number of the unreleased keyboards were sent out to customers on the east coast who had sent their original keyboards to Apple for replacement. The number of misdirected keyboards is estimated to be less than ten and all are believed to have been recovered by Apple.
At this time, MacRumors is unable to independently verify the claims. Apple last updated their input peripherals in July 2006 with the release of the Bluetooth Mighty Mouse.
Update: MacRumors has received word from an anonymous submission claiming to be from the submitters of the ThinkSecret story saying that the story is fake. Therefore in a story full of hearsay and now anonymous submissions, this rumor should be taken with a grain of salt.