Are you a Serius XM customer? If you are they just released a BlackBerry application for the newer devices including the Bold 9000, 9700, Curve 85xx, 8900, Storm 95xx, and Tour 9600. I am not sure if it will work on older devices.
The site states that you get over 120 channels of programing. FYI the service is a paid subscription, not a free service, they do have a 7 day trial but after that you will need to sign up for a paid account.
You can pick up the application by point your browser to this LINK