(According to my iPhone)
I think you can learn a decent amount about someone by the music they listen to. And if you look at someone's Top 25 Most Played Songs on their iPhone you can learn a little more, because iTunes does not lie.
Things about me: I love rap music (people laugh and think I'm joking when I say this, but I'm for real. I love great beats.); I got on this kick of really liking Bossa Nova music when I first started consulting ( wiki: a genre of Brazilian music, which developed and was popularized in the 1950s and 1960s and is today one of the best-known Brazilian music ) and it's still what I love to play when I just need to feel chill; if a Christmas song happens to pop on while I have my music on random I will listen to it - on repeat.