They actually train their people in music theory, because they pull the music apart and list a few hundred features. Depending on the genre, there are different lists of musical features that might differentiate the songs.

This is what makes Pandora unique from Last.fm, or Ping, or other "social" music discovery sites. Instead of recommending songs according who likes them, it learns what kind of music you like. It looks across genres and artists to the actual musical features of each song.

I don't know whether this has changed, but years ago when I worked there, the music analyst jobs required that you already know some music theory. (The training is to learn their system.) It's a good day job for musicians.

OK, that is good to know. I had talked to somebody about this problem several years ago and I had thought that you could start with some kind of metric space and see which songs were 'close' to each other. The guy I was talking to seemed to view the problem as a kind of Bayes Theorem problem. The example being that if you had some obscure Beatles album then you most likely had 'Abbey Road' but the inverse probably wasn't true and that is where a software service could step in ... to recommend the obscure album as one you would probably like.

One thing that I really like about the service is finding artists that seem to lead to lots of other great songs. It isn't always who I think it is. For example on a lark I put in "New Radicals" because I liked one of their songs and I was so impressed with how well that defined a particular sound. When I put in big names like the Beatles or Rolling Stones I don't think I left those stations defined for very long. I wonder is there is some kind of structure to the what Pandora has calculated that could show which bands or songs seem to be most influential.

I agree that it has a nice station feature, but I've almost completely switched to mog. For about the same price I can listen to whatever I want whenever I want and as many times in a row as I want. Their radio feature is decent as well and for only a few more bucks a month it seems a much better value. Of course pandora has a huge advertising factor that could bring in good revenue for them to make it worth the investment.

I stay with Pandora precisely because I can't listen to whatever I want, whenever I want, as many times in a row as I want. That's a whole lot of deciding and deciding takes time and effort. Pandora knows the music I like and is amazing at finding new music that I will like, without any time or effort on my part. All I have to do is turn it on. I have farmed out my music selection responsibility to them and I couldn't be happier about it.

P.S. My friends are always complementing me on how awesome my music is. I try not to take too much credit for it.

I find it sad that you have 10 points when I have 1 point, as if your statement about Pandora proves that Mog can't match up and you have never wanted to have a bit more control over your music (and that what I've said has no value). I'm not a mog salesperson. I'm a music fanatic that used to listen to pandora like crazy until I realized I could have more control and still have a great radio feature with Mog.

I want to see the future of radio be one of full choice with great suggestions, not pandora's restrictions. I think Pandora has built amazing suggestions, but it's not perfect and I want to push for the next generation of music experience.

I also checked out mog after reading your post, and it seems like a great service. My post was not meant as a critique of mog; the main point was that before Pandora, 'managing' my music was a time-consuming and tedious process. Discovering new music involved hours of browsing amazon listening to 30 second clips and trying to make educated bets as to whether I would actually like a CD or not. Making music playlists is another very fidgety exercise, especially when trying to update them with new music. Pandora solved all that for me, and for free! If I decide the ads on Pandora get to be too much, I might consider trying out mog, but for now I have very little motivation to switch.

That's fair. I think a large part of why you're not getting more upvotes is that Pandora seems to be far more popular than MOG. I hadn't heard of MOG until you mentioned it. I went to their site, and (assuming their suggestion engine and library is about as good as Pandora's or better) it seems to be all of the things I wish Pandora would be.

FWIW, you've caused one rabid Pandora fan to give it a look.

I feel like they could make a crapload of money if they sold/licensed their music selection technology/music information database. It would make their own streaming radio mostly irrelevant though.

this was the original purpose of pandora, back when it was known as "savage beast."