How CNN's Hologram Interview System Works

Last night, CNN debuted its latest ultra-high-tech gizmo: a "hologram" interview system that allows Star Wars-like images of distant people to appear on stage, interacting with the CNN host. Now, it turns out that the "hologram" isn't actually visible to the host (it's composited into the image you see at home by a computer), but it's still pretty neat. Here's a video of Will.i.am appearing "live via hologram" in the system's first use:
Okay, so how does this work? Gizmodo tells all. From the Gizmodo article:
On the subject's side: • 35 HD cameras pointed at the subject in a ring • Different cameras shoot at different angles (like the matrix), to transmit the entire body image • The cameras are hooked up to the cameras in home base in NY, synchronizing the angles so perspective is right • The system is set up in trailers outside Obama and McCain HQ • Not only is it mechanical tracking via camera communication, there's infrared as well • Correspondents see a 37-inch plasma where the return feed of the combined images are fed back to them. Useful for a misplaced hair or an unseemly boogar • Twenty "computers" are crunching this data in order to make it usable
Help us, Will.i.am, you're our only hope!
Update: as commenters noted, actually correspondent Jessica Yellin was the first to appear in "hologram" form. Here's that video.