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CBS Apologizes for Exposed Janet Jackson in Halftime Show.

Yahoo has several photos before, during and after the flash. Some news stories report that Timberlake "accidentally ripped co-performer Janet Jackson's top". Other accounts assume the flash was intentional and preplanned.
Michael Jackson's little sister ended a number titled "Rock Your Body" by allowing Timberlake to rip away the leather cup covering her breast, as they sang: "Gonna have you naked by the end of this song."
The split-second exposure, witnessed by up to 100 million viewers, revealed what appeared to be a sun-shaped metal ring atop her nipple. [...]
While CBS officials pleaded ignorance on the antics, the entertainer had hinted she was planning something outrageous.
Here's the MTV article from January 28 wherein "shocking moments" were promised for the halftime show.
MTV, CBS, Jackson and Timberlake all apologized afterwards. Timberlake's apology is pretty damn funny, intentionally or otherwise.
"I am sorry if anyone was offended by the wardrobe malfunction during the halftime performance at the Super Bowl. It was not intentional and is regrettable."
On behalf of the vast majority of viewers who didn't find a brief glimpse of a beautiful woman's breast the slightest bit offensive, let me say . . . no apology necessary.
UPDATE: Under discussion at Fark and Metafilter.
More images of the boobie seen round the world.
The high-resolution shots show off some funky nipple jewelry not visible on normal TV.

A couple of online stores displaying nipple shields like the one Janet Jackson was wearing:
Matt Drudge claims, "Top CBS executives approved a musical skit where Janet Jackson would expose her breast during the MTV-produced Super Bowl half-time concert." He cites a single, anonymous "well-placed source" for this claim. I'm skeptical. Drudge has a history of passing along disinformation aimed at making his ideological enemies look bad.