Until satellite has a viable local sales machine and until they are far more pervasive in automobiles, they will not be a big threat. Research shows that people who have satellite radios spend more time listening to their terrestrial radios anyway. They can chip away from TSL somewhat, but as a reach medium they are nowhere. The only medium that can compete with radio is TV.
To Rac's point about bleeping merger news, that's just silly. Probably some producer reacting to an old edict not to allow discussion of XM and Sirius on the air. It probably originated before Stern departed. This is news for goodness sakes - can they really be that afraid that people are going to jump in their cars and go buy radios now that the DoJ has passed the merger?
Well, for starters, I purchased a Sirius satellite radio, installed it into my vehicle and listen to it exclusively. On a side note, this is a forced decision because my car radio no longer has an antenna to pick anything up. I find myself being quite surprised that I don't miss local radio. I guess it just goes to show you how far quality programming (and those neat little tickers) will go.
As far as the bleeping... can't imagine why they would do that unless the CBS radio ouerve made it seem like sound policy. Yep, they're very scared.