To the tune of just $12.5 million, the Federal Communications Commission on Friday wagged a white-gloved finger at four top radio broadcasters -- Clear Channel Communications Inc. (NYSE: CCU), CBS Radio (NYSE: CBS) (not CBS's best week), Entercom Communications Corp. (NYSE: ETM) and Citadel Broadcasting Corp. (NYSE: CDL) -- resolving a two-year payola investigation. "A breakthrough and a milestone" in the war on payola, FCC Commissioner Jonathan Adelstein called the settlement.

The FCC's longstanding regulations don't actually prohibit the pay-for-play system, they merely require its disclosure at the time of broadcast. Said Adelstein, "These rules are based on the basic principle that listeners and viewers are entitled to know who is seeking to persuade them so they can make up their own minds about the content."

Such a principle is hardly "basic," and ignorance of sponsorship gives no pass to indiscriminating radio listeners. Marketing pays our fare at every turn; we've become resigned to the notion that behind every song we hear, every TV image we view, every word we read (including these), a dollar sign usually lies quietly. The trick to Adelstein's basic principle is not in knowing who's paying the piper -- or who the piper's paying, in this case -- but in quieting one's cynicism enough to hear the music.