Programming differences between Sirius (SIRI) and XM (XMSR) remain a fierce area of debate for partisans of either satellite radio service. Libby Pelham has a good basic write up for those considering subscribing to one or the other. Those considering either stock as an investment for the first time will want to take a look. She makes one slight mistake however, say NPR is "only" on Sirius. I'm sure she means on only Sirius of the two services, because, of course, NPR is available on terrestrial radio throughout most of the U.S. XM also carries content available free over the airwaves, such as Air America, the liberal talk network broadcast terrestrially in (shall we say) select markets.

Carrying non-exclusive content on the subscription services is a huge value. With next-to-unlimited channels available, these offerings to not shunt aside original content, and the convenience, familiarity, and a consistent signal, mean that this type of programming enhances the brand value of the service -- whichever you may prefer to consider , whether as subscriber or investor.

Michael Canfield is a private investor, a business and media writer, living in Seattle. He doesn't own stock in Sirius or XM.