Dr. Jason Rentfrow, who led the study, says that "we get a very strong impression about someone when we ask them what music they like," and that revealing what you listen to can “reinforce stereotypes and, potentially, social prejudices” about you.
Well, duh. Don't we always judge people on their preferences in movie, music, TV, and books? Isn't that why things we like but view as lowbrow are called "guilty pleasures"?
I must admit that sharing your playlist with someone is an intimate thing, but I don't know that shielding everyone from your musical opinions is the answer to not being judged — I say go forth and share.
Have you ever been afraid to share your playlist with anyone?