Music is the key...songs in the key of life...and all that jazz...
What a fascinating thread this has become. And since music is a huge part of my life, can't imagine life (now) without it, I wanted to add a couple of other notes:
Sometimes our musical appetites are influenced by prejudices and moods.
Prejudices -- We can be prejudiced for or agin certain songs, or even certain genres of music. Two examples: growing up (early 60s) I used to hear lots of country music, along with plenty of pop, British Invasion stuff, rock n roll, Motown, California dreaming, folk, funk, blues, jazz, and lest I forget plenty of religious/Christian hymns and Christmas carols. I enjoyed it all for the most part. But the country music was usually played by my father who at the time was part loving, caring, good father and family guy, and part violent, raging, mean-spirited drunk. While much of the country that I'd hear was on the radio, it was also the only music that my father played at home, and I still have images of him getting sauced and sentimental, while singing along to some of the whiniest, and most sentimental (self-pitying) country music. Needless to say, I developed a strong dislike for country music; and it was years before I came around to realize that I really liked some of it; nowadays I can even hear some of his old-time favs and happily sing along, without cringing, even enjoying some of the whinier, sappy ones. Best of all, since I opened myself up to it, I've come to know and appreciate more and other country music; most of it "old school" or classic country though since most modern country has little appeal to me. And though I'm hard pressed to name a modern country artist, I'm certain that there's some good modern country music still being made.
The 2nd example of prejudice for or agin music is something I've observed in other people. There are some who listen to ONLY this genre or that, to the exclusion of other genres. So be it! However I do find it peculiar that sometimes these same people, some of whom do have eclectic tastes, consider themselves to have open, broad-minded tastes in music, while dismissing entire genres that they have barely sampled. Their minds are closed for whatever reasons, and they summarily ignore, even hate an entire genre, without giving it a fair hearing.
Moods -- Taste in music also seems to be mood "dependent". My musical appetite is all over the map, though like most I have my favs. And in addition to the music I listed above, I've come to hear and enjoy some classical, disco, techno, fusion, reggae, soca, hip-hop, rap, etc... And there are times when I'm not in the mood, for even a favourite song or artist.
Something recently happened (happened before too) that I'll use to illustrate this:
I was in the kitchen cooking dinner. No music on. My son came in, turned on the radio and a song began playing. I started dancing around the room spontaneously, as I'm inclined to do, enjoying the song, its rhythms, the beat, the tune. When it stopped, I looked at my son and asked "That was good, who was that?" He had a big grin on his face, said, "That's 50 cent!" and started laughing. I returned, "No way!". Then I started laughing, adding "Well I still don't like him". Because I'd said before that I don't like 50 cent. Once used to sing along to his first hit, forget the name. Very catchy, mindless, dance tune. But, his whole I'm a thug, I'm a gangsta, pimp, whateverrrr, got irritating really fast. Btw, my 21 yr. old, listens to lots of reggae, hip-hop, and rap, including some gangsta rap, and he enjoys and sings along with some oldies too, pop, Motown, rocknroll... And fortunately, he's pretty level-headed and has not been seduced by the gangsta/thug image and culture. He sees it for what it's worth. Ditto for most all of his friends.
So, it seems that not only can mood influence our musical appetite, but that even a disliked artist (in this case 50 cent) can influence our mood in a positive way. I can almost guarantee that if I'd heard the radio dj announce that the next song was 50 cent, that I would have tuned it out.
Which brings me back to the question of prejudice, even though I've determined through listening, not just sampling, that I do not like gangsta music and consider it to be damaging and dangerous, that I wouldn't spend 5 cents supporting it, I can't even summarily dismiss 50 cent's music as total crap, cause I did enjoy that tune. Didn't pay attention to the lyrics btw, don't think I missed much 
Oh, and another genre of music which I don't like is metal. I change stations whenever I hear or see Metallica, for example. But, I guarantee that at the right moment, in the appropriate mood, I swear that I could enjoy a Metallica moment.
FWIW, that's my fiddy cent contribution to this thread.
(My first 