It's time to address the 800-pound gorilla in the room. A year from now, Howard Stern will be at the end of his five-year deal with Sirius XM Radio (NASDAQ:SIRI). In a tactfully prudent move, satellite radio's biggest celebrity has yet to divulge his plans for 2011.

Will his contract be renewed? If his deal is extended, will the terms be for more or less money and for more or less time on the air? Can satellite radio survive without him?

Stern has options
For Stern, things aren't as black and white as a choice between terrestrial or satellite.

Traditional radio has faded in Stern's absence, as even folks who haven't migrated to satellite radio have other aural alternatives, including music and podcasts through portable media players and a growing slate of programming options that can be streamed through smartphones and other Web-enabled devices.

Satellite radio's audience has grown, but Sirius XM may be reluctant to match or exceed its original offer of $500 million in cash and stock for five years.

Stern will turn 57 in January 2011. That isn't necessarily old by radio standards, but it's not as if he needs the money, either. If he re-ups with Sirius, it will probably be for less time, considering how he already spends fewer hours on the air now than he did during his days at Viacom (NYSE:VIA).

In an ideal world, Stern would elevate himself to more of an overseer role, but the shame there is that he hasn't exactly mentored a fleet of potential replacements. He has padded his Howard 101 channel with capable bad boys, including Bubba the Love Sponge and Scott Ferrall, but in the end, this is a situation like Berkshire Hathaway (NYSE:BRK-A) (NYSE:BRK-B) after Warren Buffett or Apple (NASDAQ:AAPL) sans Steve Jobs.

Stern's biggest crime is that he became too good at what he has done, to the point that he's indispensible. If so, he also has a third option that would shun both terrestrial and satellite radio entirely.

Stern's Oprah moment
Oprah Winfrey is also spreading her wings come 2011. She's leaving her show, although she's likely to land on higher ground as part of her Oprah Winfrey Network deal with Discovery Communications (NASDAQ:DISCA). The seeds have therefore been planted if Stern chooses to go it alone.

One of the reasons Sirius XM's streaming application through Apple failed to move the needle was the lack of Stern. His contract excludes streaming through wireless devices. How many more people will own smartphones come 2011? Will there be enough for Stern to launch his own premium app? If he can get a million diehard fans to pay $8.33 a month for app access, that's a $100 million gross right there, before we begin to consider sponsorships and other revenue-generating possibilities. He's been given plenty of autonomy at Sirius XM, but this would be his empire entirely, as he once again would ride the hot media trend of the moment.

It may never come to that, but trust Stern to play that card in negotiating with Sirius XM. After all, there may not be too many people interested in paying $15 a month for Sirius XM if they're paying nearly $10 a month for access to Stern.

The math of the future
Sirius and XM threw a lot of money at Stern, Winfrey, the NFL, and Major League Baseball when they were competing against one another. The merged entity still couldn’t call all of the shots in a negotiation, but since the bidding wars are over, Sirius XM at least has an improved position.

Professional sports have launched standalone apps and online streaming subscriptions, and larger radio celebrities may very well follow suit. Again, it's no longer about terrestrial versus satellite. Both of those platforms are also competing against growing access to online connectivity.

In the end, Sirius XM could survive Stern's departure come next December if it gets to that point. The improving cash flow is the real deal, and even subscribers who initially came over during the Stern migration should concede the value of the available programming.

However, if Stern's departure sparks the breakout of niche streaming content, that's when satellite radio as a platform will be tested.

The future is so open-ended -- and never boring.

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Longtime Fool contributor Rick Munarriz is a subscriber to both Sirius and XM. He owns no shares in any of the stocks in this story and is also a member of the Rule Breakers analytical team, seeking out the next great growth stock early in its defiance. The Fool has a disclosure policy.