Most Helpful Girl
It doesn't mean much to me, no. Having a common taste--or, even better, a shared burning hatred--for certain music can make someone I'm already attracted to /slightly/ more attractive, but someone's taste in music will never be a deal-breaker or deal-maker.
Most Helpful Guy
To me, it doesn't really matter. I you really fall in love with someone, then music is just a tiny detail. It's great to share the same passion of music, but it is not the end of the world when it doesn't. To me though, I like to listen to old music, from 1950s to early 2000s, so it's kind of rare to find people who do like I do. So I tend not to depend a lot on the music "factor", but more on the appreciation of each other, and which other music she might like. There's always one song that could be liked, if you're open to it.