I recently asked a friend if she knew a guy I’d met. “I think so,” she said confusedly. “Oh wait, no. I just know his iTunes library.”

In a world of AirPennNet and free Wi-Fi at Starbucks, our music libraries — should we choose to share them — are available for friends and strangers to explore. Like Facebook, Twitter and everything else, our iTunes libraries broadcast tailored snapshots of our auditory interests into cyberspace.

The notion of personal internet transparency is about as tired a topic as any, but I bring up iTunes because it functions somewhat differently than other publicity-me-please outlets like Facebook and Twitter. Although you do have to click some button in some preferences tab to share your tunes with others, it’s a yes/no field and you can’t select which songs you want to share.

Bored of my own Lady Gaga tunes, all of this struck me when I checked out the iTunes library of an acquaintance from the stacks of Van Pelt. I was shocked by what I found.

Unlike my Britney Spears-peppered library, the library of music I found was more manicured than my aunt’s acrylic nails. The mix between classic rock, alternative Brooklyn bands and the Beatles was in such a perfect ratio I found it hard to take seriously. Where was the sprinkling of Justin Timberlake, the Broadway show tunes, the silly song parody a friend sent two years ago?

Despite the Bob Dylan I’d gladly display, perhaps it’s my library’s inclusion of the Mamma Mia soundtrack that makes me less than willing to publicize what I like to listen to. In this case, it’s all or nothing.

The ability to cut and trim our online personalities is something we’ve come to take for granted. So when it’s take it or leave it, I, like many others, keep my music to myself.

Unfortunately for some, in the world around us, it’s not as easy as iTunes when it comes to publishing your online personality. Certainly it would have been nice for Bernie Madoff and the execs at AIG to share only the files they were proud of. My bet is that Mr. Madoff has a library full of cheesy pop music.