The Library of Congress has essentially designated the recording of George Carlin's "Seven Words You Can Never Say On Television" routine, the one that launched the FCC's crackdown on indecency, a national treasure. Carlin's 1972 album, Class Clown, was among 25 landmark recordings added this week to the library's National Recording Registry, recognized for their "cultural, artistic and/or historical significance to American society and the nation's aural legacy." John Eggerton has the story.