James Gandolfini, star of hit HBO mob drama The Sopranos, is threatening to leave the series. Tony Soprano wants a significant raise or -- bada-boom, bada-bing -- he's outta there.

It's not welcome news for HBO parent AOL Time Warner(NYSE: AOL). You don't need to check out Jon Hein's JumpTheShark.com to realize few shows thrive after the central figure bows out.

We've seen this before, of course. One day, General Electric's(NYSE: GE) NBC had six young sitcom stars making modest sums, and a few seasons later, these Friends pulled in a million apiece for each new episode.

The dynamics are different this time because Tony's mob rules on commercial-free cable TV. While NBC could command higher fees from advertisers, it's unclear if AOL Time Warner could up its subscriber fees just to keep the popular show on the air.

That's the broadcasting rub. It's not all that different from professional sports, where proven veterans command multimillion-dollar contracts. Ironically, many of these once-nimble players have peaked, and before you know it, a sports program is stuck overpaying an underachieving squad that winds up resembling last season's New York Mets or the Washington Redskins, with marquee names failing to produce marquee results.

While the TV-programming world doesn't face salary caps or luxury taxes, it does have to deal with sponsors' limited elasticity. You can pity Disney's(NYSE: DIS) ABC for its fourth-place finish in last month's Nielsen ratings, but at least it has mostly affordable content. NBC makes less off hit shows Friends, E.R., and Frasier, which just aren't as cheap and margin-friendly as they once were.

The big winners? Viacom's CBS (NYSE: CBS) and Fox(NYSE: FOX). Between Survivor and the return of Star Search, CBS climbed on top, while Fox made significant headway with American Idol and Joe Millionaire. The beauty for Fox is that reality TV is as popular as ever, and its stars don't renegotiate deals because they are inherently replaceable. The talent pool will never dry up; folks will continue to do anything, anywhere for their 15 minutes of fame.

Look out, Hollywood. Actors who want more are competing against amateurs who will take anything. But don't worry, Carmela. Gandolfini will probably get his money. This time. But out there in suburbia, tens of thousands are willing to make networks an offer they can't refuse.