Sirius XM Radio (NASDAQ:SIRI) signing up Joel Osteen in a content deal last week didn't bring the kind of Wall Street accolades that it probably should have. The market's full of heathens, it seems. 

However, this is a pretty big catch for Sirius XM. Set any religious skepticism aside for a moment. This isn't about wooing those who aren't sympathetic to Osteen's church of beliefs. The autumn launch of Joel Osteen Radio on Sirius XM is about latching on to the folks who already follow the popular husband-and-wife team.  

The global reach of Osteen's Lakewood Church is huge. It claims that its television ministries reach over 100 million homes in the U.S. and tens of millions more across 100 different nations. Sure, these are homes that merely have access to Osteen's programming. It doesn't mean that they are actually being reached. His appeal is still undeniable.  

Thankfully, we have a better metric for gauging Osteen's appeal without having to crack open a ratings book. Each week, more than 1 million people download Osteen's free podcast according to his ministry's website. A whopping 48 million audio and video podcasts have been downloaded. 

The podcast numbers aren't as high as the television ministry's potential land grab, but it's the more impressive metric. If there are really more than 1 million people tech savvy enough to stream Osteen's podcasts, imagine how many more out there would prefer to seamlessly turn on their car's satellite receivers to tune in to hear Osteen's sermons.

Isn't that the point of being in Sirius XM's position? It has more than enough channels in its arsenal to offer specialized content, just like the pay-TV providers that serve more than 100 million homes in this country. There is no such thing as a single channel that's universally enjoyed, but everyone has a couple of channels that are indispensable, so they stick around. As the only game in town when it comes to premium live radio, we're talking about 25.8 million subscribers as of the end of March. If you're putting out prolific audio content, why wouldn't you want some real estate on Sirius XM's dial? You would be reaching folks with enough disposable income to pay for radio. This gives Sirius XM some surprising leverage when it comes to wresting radio icons from terrestrial radio. 

It doesn't matter what you personally think about Osteen or religious content in general. It's incremental for Sirius XM, and likely in a major way with many of his followers that had sworn off satellite radio. This is a pretty big deal, and regardless of where you fall on the spiritual spectrum, it should fortify your faith in Sirius XM as an investment.