The phrase “Janet Jackson’s boob” is just intrinsically funny. There’s no getting around that.
UPDATE: Best. Boob. Comment. Ever. (from Atrios)
“Some day our country is going to have to take a long hard look at itself and wonder why it tolerates massive amounts of violence on TV, but a single Boob is capable of driving us collectively insane.”
I think even funnier are the labels attached to the, ummm, decoration adorning her boob.
So far, “nipple shield,” and “nipple broach” are my favorites.