I've been using Pandora.com a lot lately, when I'm on campus and don't have any of my own music to listen to. I really like it. In fact, I like it a lot better than regular radio for a number of reasons.
1. I can make a channel that plays the music I want, rather than choosing from whatever channels already exist.
2. When a song I don't like is on, I can skip it (most of the time).
3. If none of the stations that I have is playing what I want, I can just create another channel that is almost identical to the other channels, so I can basically listen to whatever I want, as long as I have enough stations.
4. If I'm listening to a song I like, I don't have to worry about missing another good song on another station, because they all pause when they come to a new song.
5. No commercials.... At least no commercials I have to listen to. It does seem like their visual advertising has become even more aggressive over time. Maybe in a few months or years, you won't be able to find the player, because its buried in ads. :( But at least I don't have to listen to the ads. Or worse: the radio hosts.
6. They've got a lot of extra features that might be pretty useful, like being able to buy the song on iTunes, and bookmarking it and stuff.
7. If I really hate a song, I can have it not play it any more! How nice is that?! Now if only I could get it to completely ignore certain artists....
I really like it right now, though the total number of possible selections seems kind of small, so I'm sure I'll get sick of the available choices before too long. Hopefully they'll keep adding new songs. If you haven't ever tried it out, I'd recommend it. So thanks Dave, for introducing it to me!
