XM on the debut of Howard Stern on Sirius:

“Our content has not changed,” said Eric Logan, XM’s executive vice president of programming. “We have a platform targeted at mainstream America. There are more and more people who find Howard Stern repulsive and offensive and will go away from anywhere he is.”

XM offered Sterm a $30m/year contract, which he turned down for Sirius. It’s not as if XM wanted him to host a series of children’s programs or something.