Facing financial difficulties, Sirius recently received a government 'green light', and merged with XM Satellite radio, essentially creating a monopoly in the US for individual and commercial satellite radio subscribers.
According to the release, "100% of the U.S. Music Royalty Fee will be used to offset payments from SIRIUS and XM to the music industry."
Details and an explanation of the new charges can now be found on the Sirius radio website here.
Update June 17 PM: Sirius is set to launch an iPhone app on Thursday June 18. The app will work free on the iPod Touch (and Wi-Fi). Others will pay approx. $3/month in the US.