*Splutter* How much?
From the this-is-ludicrous camp, quoted from the excellent gearlog blog:
I am an XM customer and am a big fan of the service. I believe the fundamental XM business remains solid. I am more concerned for Sirius, which is paying Stern $500 million over 5 years to air his daily trashfest. If the new Stern subscribers don't appear and then hang around, Sirius is in deep trouble 
Half a billion dollars? Someone, somewhere has seriously lost the plot..