While driving around today, I noticed that reception on our XM radio was pretty spotty. I just saw this post that mentions that one of XM's satellites is not working correctly, and their repeaters having problems.
Update: It looks like the problem has been solved. Here is an email I received from XM:
XM Radio Resumes Normal Levels of Service
XM Satellite Radio has resumed normal levels of service for customers who experienced outages or significantly degraded service starting yesterday.
The problem occurred during the loading of software to a critical component of the satellite broadcast system, which resulted in a temporary loss of signal from one of the company’s satellites.
After you turn on your XM radio, please allow five to ten minutes to reacquire the XM signal.
XM apologizes for any inconvenience this has caused.
Here is a Frappr map of reported reception problems: