Internet radio is still too weak to make much of an impact in the automobile, leaving only broadcast radio which speaks for itself.
This won't be the case in the future, due to tech advances, and even in the near term, streaming via 3G and 4G and plugging into a USB or other means, to a radio in the automobile.
As advances in technology increase, look for other avenues to stream to autos as well. We are. at no means, at the end of the tech bubble.
Currently it is a hassle though. I listen to Slacker in my auto, but it isn't as easy as I would like and I have no doubt many wouldn't bother. Only full integration will allow internet radio to make a strong run at satellite and broadcast radio, and it will take a while before autos with included internet radio are mainstream.
An interesting statistic was released at RAIN today. 90% of all Sound Exchange royalties for 2011 are from Pandora and SiriusXM. The remaining 10% is made up of everyone else. Clear Channel, CBS, all other terrestrial streams, cable radio stations, the 10,000+ streaming stations, etc. It has been estimated for a while that Pandora serves roughly half of all measured internet radio listeners in the USA on an average day. 50% of all streaming plus the cable networks should equal a lot more than 10%. Does anyone else find that a little strange? RAIN doesn't come out and say it, but it looks to me like a lot of people simply are not paying as much as they should if they pay anything at all. This is very damaging to Pandora and internet radio as a whole.
http://kurthanson.com/news/macdonald-%22staggering-figure%22-suggests-pandora-siriusxm-have-%22-good-deal-leverage-extract-fair-