Not sure which. Last I knew, GM was going with XM, Ford or Chrysler is an investor in Sirius (forget which).

I do know that Porsche was going to give buyers the option of which one.
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"Nature has constituted utility to man the standard and test of virtue. Men living in different countries, under different circumstances, different habits and regimens, may have different utilities; the same act, therefore, may be useful and consequently virtuous in one country which is injurious and vicious in another differently circumstanced" - Thomas Jefferson, moral relativist