General Motors recently signed up its one millionth XM satellite radio subscriber.

GM was the first OEM to offer factory-installed satellite radio and now offers more than 50 car and truck models with the feature.

The first XM-equipped vehicles, Cadillac DeVilles and Sevilles, were produced in November 2001 and the one millionth vehicle rolled off the line in February 2004. One out of three GM vehicles purchased now are equipped with factory-installed satellite radio.