Sirius (NASDAQ:SIRI) and XM (NASDAQ:XMSR) are in agreement. They want to get hitched. Shareholders of both companies voted in favor of the proposed union in separate meetings yesterday, nearly nine months after the banns were read.

Not so fast with that tuxedo rental, chum. Just because our digital Romeo and Juliet want to join forces doesn't mean that parental regulators will sign off on the deal.

That's where this analogy comes undone like a bridal gown in a honeymoon suite. Sirius and XM can't just ignore the naysayers and elope. They can't run off in the middle of the night to some Elvis shrine/chapel in Vegas, hoping to return in a few months to prove the critics wrong.

If the regulators block the deal, XM and Sirius are back at war.

This has certainly taken a long time. A lot of credit for that goes to sharp, proactive moves by Sirius and XM; if you think about it, this deal should have been killed months ago.

The original agreements under which XM and Sirius were birthed prohibited a merger. Love can make you do some pretty silly things, though -- especially when billions in potential synergy savings are at stake.

XM and Sirius knew that they were dealing with a vindictive cop grappling with an itchy trigger finger. One false move, and the deal would have been blown to bits. Instead, XM and Sirius went beyond what was required. They formally proposed wider packaged content variety and lower-priced plans. They also guaranteed that old radios will never become obsolete.

In short, they swept the bearish argument rug from underneath the terrestrial-radio objectors. Instead of coming off as the voice of reason in honoring a 1997 agreement that created the satellite radio industry, the National Association of Broadcasters sounded like a collection of party poopers.

It's probably telling that if you go to NAB's XMSiriusMonopoly.org website, the last media report listed on the site as backing its antimerger position is a Bloomberg article from April. A lot of consumer-friendly concessions have been made by XM and Sirius since then, not to mention changes in the way that aural content is consumed.

Subscription services like Napster (NASDAQ:NAPS) and RealNetworks (NASDAQ:RNWK) -- along with countless music discovery sites -- are arming music lovers with virtual jukeboxes loaded with millions of tunes. Apple (NASDAQ:AAPL), Microsoft (NASDAQ:MSFT), and SanDisk (NASDAQ:SNDK) are trying to out-groove their rivals with portable solutions. (See Microsoft's latest move here.)

The world has clearly changed over the past 10 years. It's even changed plenty since the heyday of the merger critics earlier this year. So what's holding up the nuptials, FCC? The next hoop you put XM and Sirius through better be a wedding ring.

Other things to read before the wedding invitation arrives:

Microsoft is an Inside Value recommendation.

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