At the moment the two systems have similar music channels, the major difference comes between the sports programming. XM's got baseball and Sirius has NFL/NBA/NHL/Nascar. Personally I wanted Howard Stern and that's why i've gone with Sirius, even though i'd like to be able to listen to other baseball games besides the home teams. XM also has a truely portable device, while Sirius has one coming out this summer. (haven't read reviews yet) Don't know about XM, but most of Sirius' channels are available through an internet stream.

XM has made several big name deals (Oprah's 1/2hr per week for instance) and is having some cash problems, and more of their music channels now have some commercials. This trend should bother XM users. But if you want a cheap XM plan, sign up, then threaten to cancel. Many people are getting great deals to just stay on.

I wouldn't have bought a satellite radio if it wasn't for Howard. I find most of the music channels nausiating, it's the same crap from the radio, just without commercials. It's definitely a luxury item. But for fans of Howard it's unbelievable. the shows are now almost 6 hours long and maybe 10 minutes of commercials in that 6 hours instead of the 18-20 minutes per hour which occured on terrestrial radio. Being able to hear people speak their minds without having to bow down to nebulous community standards regulations set up to limit adult conversations is wonderful.
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