It was originally built as a hack. For example, the interns taught the technology to shut off when it detected someone flipping the camera off, or waving goodbye.
Apple decided it was worth holding. When the original MacBook and iMac computers came with a built-in camera, our source theorized that's what the original intent was.
Apple didn't go that route, but there is still one other route that they can take the technology — the new Apple Television. (We're talking about the actual television, not the hockey puck device.)
Apple has a good incentive to include it, too — its primary competition for the living room, Microsoft, has a motion controller connected to just about every home entertainment device plugged into the TV.