I wouldn't attribute the princess phenomenon to anything more sinister than casual sexism: "Oh, you're a girl, girls like princesses, here's princesses for you." Ditto boys and superheroes.
My DD10 has liked Ariel for years (who starts out by rescuing the prince) and sees a lot of herself in Elsa (keeping in her emotions while bored out of her skull in class, and hiding her abilities), but otherwise thinks most princesses and their stories are stupid. DD is drawn to fiction with strong female leads: Hermione, Katniss, Tris. And, because nobody is practicing casual sexism in my household, she's also a fan of superheroes, particularly the whole Avengers franchise.
Our DD is exposed to a lot of stuff her peers wouldn't be into, too, so it's not like she's immersed in current pop culture. DW and I don't have much common ground on music, so we're both exposing DD to very different kinds of music, and very little of the stuff I'm listening to can be found on the radio. DD is currently on a Tom Hanks kick, so while we have to screen/fast-forward for inappropriate content (Forrest Gump is a few years away), in recent months she has watched and re-watched Apollo 13, Castaway, The Terminal, and Big.
The important thing about pop culture, though, is to, as I said, drag the ugliness out into the light and point out all its features. DD has had conversations with us about why those other princesses are stupid. We've all agreed that the lead character in Victorious is the least-talented female vocalist in the show, and we've discussed why she got the lead anyway, and how she represents unhealthy, unnatural body images. This is how we're countering the horrible messages society subtly and not-so-subtly conveys to impressionable young girls.
Like aquinas, this topic does twig my feminism, too. If you're the father of a daughter, you either become a feminist, or you rhyme with glass pole.
