NEW YORK - CBS apologized for an unexpectedly R-rated end to its Super Bowl halftime show, when singer Justin Timberlake (news) tore off part of Janet Jackson (news)'s top, exposing her breast.The two singers were performing a flirtatious duet to end the halftime show, and at the song's finish, Timberlake reached across Jackson's leather gladiator outfit and pulled off the covering to her right breast.The network quickly cut away from the shot, and did not mention the incident on the air.Timberlake said he did not intend to expose Jackson's breast."I am sorry that anyone was offended by the wardrobe malfunction...