http://www.dbstalk.com/showthread.php?t=48151
Sadly, no. If XM had ESPN radio, it'd be a no-brainer. As it is...well, it's still probably a no-brainer, with the MLB package and exclusive rights to hockey starting in 07-08.
I can't see getting Sirius for the NFL and NBA packages, since I'm always in front of the TV for the NFL and I hate listening to basketball on radio.