This clip, which has been making the World Wide Web rounds this week, demonstrates how Katie Couric and Dan Rather have more in common than struggling to compete with NBC. But how does a clip like this – where a feed is recording, but not even broadcasting to CBS affiliates – even end up on YouTube?

"Easy," says a TV news industry veteran not at CBS. Though the feed was likely kept "isolated … and kept inside the building" to protect against slip ups exactly like this one, "any edit room can call up the control room or even sometimes a camera," pull the feed into an Avid machine, and then email or upload the file anywhere. "We're very careful about isolated feeds," says our source.

But the culprit would almost certainly have to be "somebody within CBS." Although the feed "may have gone out over satellite by mistake, because that happens," most likely it took place in the building, and not even at a CBS affiliate, whether in Philadelphia or Los Angeles.

And will they find the person who's out to embarrass Katie? Probably not. "It'll be really hard to track it down" and know which machine the feed was pulled from.

Though certainly fingers will point at Leslie Stahl sympathizers.

Update: Brian Stetler has an interview with Harry Shearer, the man behind the video's debut.

Meanwhile, as some have insisted, "it's possible the clip came from CBS but lots of people just cruise the cable channels and are capable of downloading stuff through the airwaves," relays a CBS source. "It can be individuals with very rudimentary access who can download stuff that is being fed from around the country."

And as for Katie's reaction to the whole thing? "Katie's not at all embarrassed — in fact she's happy that it makes it known she's having some fun." It's as if Matthew Hiltzik put out the video himself!