We call them earnings reports, though in the case of fledgling satellite radio upstarts XM Satellite Radio (NASDAQ:XMSR) and Sirius (NASDAQ:SIRI) we know that their quarterly updates are more like status reports. It will be some time before either company becomes profitable.

However, the potential is clearly huge as the two companies have a massive potential market to carve between themselves. Both service providers have been growing their subscriber base quickly -- as well as widening their already deep lineup of programming channels. This week, it will be XM announcing its June quarter results.

With more than 2.1 million subscribers, market leader XM's growing popularity is not the problem. The rub lies in the red -- the company posted a loss of $584.5 million last year. Yes, the fundamentals are improving, above and beyond the user count. The deficits should continue to narrow. The average acquisition cost for each new subscriber is falling. Both XM and Sirius have a long way to go, but at least they are heading in the right direction.

We'll know a little better how well XM is sticking to that path after it reports Thursday.

Other familiar companies will be posting earnings this week. From Sara Lee (NYSE:SLE) to Panera Bread (NASDAQ:PNRA), from Orbitz (NASDAQ:ORBZ) to Tyco (NYSE:TYC), the quarterly reports are coming loud and clear. XM (and Sirius, for that matter) would have two words of advice: Tune in.

Are XM and Sirius misunderstood or overvalued? Have you checked out satellite radio? What did you think? All this and more -- in the XM Satellite Radio discussion board. Only on Fool.com.

Longtime Fool contributor Rick Munarriz would gladly broadcast his opinion on more than 100 channels of digital radio -- if only someone would listen. He does not own shares in any of the companies mentioned in this story.