If you are like me and don't have XM or Sirus on your boat, here's a cheap (free) solution. Pandora and or Slacker for the iPhone. Pandora is a little more user specific. You can search for specific artists, songs etc... and create your own station based on these searches. They have OK stock stations but not great. You really need to customize and build your own station. Slacker has a little more of a slick interface that incorporates a coverflow like experience where you can swipe to the next song. Much better pre-programmed stations, very much like a XM experience. You can still search for specific songs or artists. I think both sound really good for streaming music, maybe Slacker sounds a little better, comparable to satalite radio. The free version of slacker only lets you skip 5 songs within an hour and has a 5 sec slacker commercial every 3 or 5 songs. The plus version has unlimited skips and no commercial for $3.99/month. Both seem to take a few seconds to buffer between songs. Once you get rolling, both can drop audio if you are on a busy wifi or a week edge network. 3G seems to work fine. I've heard the next system update will allow you to run more than one program at a time. So you can run say slacker and GPS or navigation software at the same time. If you have a jailbroken phone, you can do that now with an app called backgrounder.