what exactly is HD radio? I've seen that advertised.
I find it sounds better than regular radio on my aftermarket headunit. However, if the station hasn't sync'd (I'm not sure on the correct term) their HD and their regular radio, you get an annoying back and forth. I find the HD lags a few seconds. So when it fades in and out, it gets annoying as hell in short order.
As far as paying for free internet radio...that is debateable. Sev brings up a good point. You're already paying for the internet...or your phone and data plan. In VT, we pay $20 a month for cable interweb. That bill gets paid no matter if we use the internet for 10 minutes on a weekend...or for 16 hours a day for two days straight of streaming music.
I find Pandora isn't that bad for commercials. Slacker was getting really bad. Plus, they had that darn "nag" screen asking you if you were still listening every hour. That was weak when we had the radio on inside and were listening outside doing yardwork. Pandora now has some commercials, but I find they're not nearly as frequent as Slacker.