Decision Day is looming for Sirius (NASDAQ:SIRI) and XM (NASDAQ:XMSR).

Regulators have spent the past nine months debating the proposed combination of the country's only two satellite radio operators. A recommendation might be made in the next few days that will either derail the merger or create a premium programming force with more than 16 million subscribers.

Several factors are tugging the Justice Department in different directions. Let's explore them quickly before I hand over the soapbox to you. Yes, you.

Just say no
Critics of the deal argue that the merger would transform a duopoly into a monopoly. Sirius and XM may not be the only satellite radio providers on the planet -- WorldSpace (NASDAQ:WRSP) is a fledgling provider outside the U.S. -- but they are the only two with domestic licenses. The original language that awarded the two contracts prohibits a combination.

Consolidation fears come into play, of course. If one company is watching over both brands, consumers may be denied lower prices, enhanced programming, and responsive customer service and other elements that are the logical byproducts of a competitive landscape.

Just say yes
Proponents of the deal argue that a chunk of the billions in realized synergies will be passed on to subscribers. In fact, XM and Sirius have already committed to rolling out low-priced plans and flexible programming packages within a year of the merger's completion.

Fans of the deal also point out that the marketplace has changed. The FCC may have shot down merger plans of DIRECTV (NYSE:DTV) and EchoStar (NASDAQ:DISH) in satellite television five years ago, but audio content is plentiful in today's world of iPod-enabled cell phones and Internet radio.

Back to you
What do you think? We Fools have added comment boxes to some articles to give you a soapbox to agree or disagree with the articles on the site. This is an incendiary topic, so feel free to chime in.

Why do you think the deal will happen? If it doesn't happen, will it matter to the market? How are you playing this as an investor?

Scroll to the bottom and kick in with your thoughts on this courtship that is barreling quickly to a resolution.

Once you're off the soapbox, check some more articles on the merger:

XM is a former recommendation of the Rule Breakers growth stock subscription service. Want to read it for free heading into the holidays? Go for it with a 30-day trial subscription.

Longtime Fool contributor Rick Munarriz is such a satellite radio fan he subscribes to both XM and Sirius. He does not own shares in any company in this story. He 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.