My new Jeep came with a Sirius enabled receiver and a years subscription to their service.

It was good that it came pre-installed because I couldn't see a compelling difference between the two services (Sirius and XM) although XM does seem to have a wider offering including the XM NavTraffic GPS receiver and the XM+Napster service (though it doesn't let you bookmark tracks in the car which is a big omission)

In terms of content though there doesn't seem to be anything to differentiate them - I want to listen to music in the car, not people talking so my criteria is possibly already a little limited (given the push both of them have to sign up big name celebrity hosts).

So, I've been listening to the music channels (mostly 33 through 53) and it's pretty average. No outstanding programming but I do enjoy the lack of adverts and (on the whole) inane chatter.

I do notice a fair amount of "no signal" though driving around Redmond, and the fact that (unlike FM) it cuts out in parking garages is really irritating.

The other thing (that the receiver does in FM mode) that's missing for the Sirius experience is track info on the display. When I'm listening to something like Chill that often plays tracks I don't know it would be really nice to get a clue as to what I'm listening to.

The car came with a 12 month subscription so I've got a while to decide if I can live without it, or if XM has better hardware/coverage and I want to rip out the stereo and retro-fit (though by then if NYTimes is right they may have merged and the problem become moot).

In an ideal world (similar to the issues facing Online TV) a good one-stop solution would be available. One subscription plan giving access to all content for streaming and download, be it in the car, on my Media Center, my cellphone, my laptop or a stand-alone radio. From any device I'd be able to tag tracks for later replay and/or purchase (and provided I can listen to them anywhere I want, when I want, how and in ten years time - I don't care what DRM gets wrapped around them). My perfect solution would also provide access to audiobooks for it to really be music to my ears (but there's another bunch of providers who, like the ebook vendors, need to settle on a common platform rather than half a dozen competing platforms) - so I can start listening in the car on the way to work, continue to listen on my PocketPC phone at lunchtime and catch up with another chapter at night from the receiver in the bedroom...