On Sunday the Israeli publication Calcalist (Google translation here) reported that Apple has purchased a company called PrimeSense, which makes chips used in 3D motion-sensing and computer vision. Their technology is used in Microsoft's popular Kinect (see image accompanying this post), which lets users of Microsoft's Xbox video game console and Windows PCs control the devices and play games just by making motions in the air. The article speculates that Apple will use the technology in conjunction with the rumored HDTV that Apple has been said to be working on. And it notes that Apple does indeed have patents regarding controlling a TV via motion sensing.
PCWorld refers to the PrimeSense technology as "opening Siri's eyes." I like the analogy. And they speculate that it could be used for facial recognition in the iPhone. The article also says that Apple is reportedly exploring using motion sensors to track customers as they move through Apple Stores in order to see which products attract their attention.