I've said this before...terrestrial radio will always do better than just about anything else* for local news, weather, traffic, sports, local talk, and full-service/community affairs/HS sports, because of the ubiquity of radio sets and the limitations on satellite channels. You get D1-A (FBS) college and major league pro games on satellite, but not as much sportstalk, and forget about FCS college games or minor league pro games. Even in larger markets, satellite traffic and weather is a joke. You get reports immediately (not just at the top and bottom and on the fives), but they are often stale.
Similarly, terrestrial radio will always have a market among those without the means to pay for pay-radio or a wireless provider, such as ethnic markets (country, urban, Latino) and teen markets (alt, active rock, CHR).
*Having said that, I believe that satellite will be threatened by software defined radio (radio over wireless IP, such as WiMAX, etc.). People will quit paying for satellite when they can get it for "free" (or cheaper) over IP.
A friend of mine, who runs Play By Play Advertising (
http://www.playbyplayadvertising.com/ ) used to run HS sports on Lake 102 (before they got sold and flipped to Latino), and also on local cable channels. Problem was, cable was too expensive, it was hard to sell spots across multiple cable companies (Charter, Comcast, and Adelphia, not counting multiple offices with different channel lineups), and if you had dish you were SOL. He has now gone strictly online--you can stream games live or download podcasts. Now anyone with broadband (even mobile broadband) can get his broadcasts.
Terrestrial radio will survive (including HD Radio, if iBiquity can get their act together and market it as aggressively as satellite has). Satellite will be a niche market in 10 years, relegated to those without reliable access to a wireless broadband Internet connection (rural customers, long-haul truckers, etc.--similar to DirecPC for broadband Internet)--although it's not impossible that Sirius XM could transition customers to a hybrid satellite/IP product. IP radio will be what does satellite in, with its choice of "free" and listener-paid options, including the ability to pick and choose those stations you pay for, as opposed to buying a package. Imagine a radio that could pick up streams of terrestrial stations, HD subchannels, satellite channels, and Internet (only) stations.
To Roddy's point, wireless broadband Internet good enough for streaming will have decent enough coverage (in large metro areas, along major interstates, etc.) in about 5 years, I'm guessing, with wide enough coverage to be a serious player in 10-15. It will come sooner than you think, if the economy permits.