http://blogs.strategyanalytics.com/auto/?p=122
"While satellite radio is increasingly optional either from the factory or in the aftermarket, HD Radio is increasingly standard equipment on cars. But the real killer for Sirius is unfolding in recent meetings with OEMs. Sirius has told its clients, which include BMW, Mercedes, Chrysler, Ford, Kia, Land Rover, Jaguar and many others, that they must switch to XM by 2016. For the car makers that helped make Sirius XM what it is today, there are no special subsidies, no silver bullet hardware fix or retrofit. There is simply a notification that they must switch from Sirius to XM by 2016."