"Girl"-y Books

Thanks to The Girl with the Dragon Tattoo, there are now way too many books out there with the word "girl" in the title. Here are just a few I've noticed:

• The Girl In the Polka Dot Dress by Beryl Bainbridge
• The Girl Who Was on Fire: Your Favorite Authors on Suzanne Collins' Hunger Games Trilogy
• The Girl Who Disappeared Twice by Andrea Kane
• The Girl Who Circumnavigated Fairyland In a Ship of Her Own Making by Catherynne M. Valente
• The Girl In the Green Raincoat by Laura Lippman
• The Girl In Alfred Hitchcock's Shower by Robert Graysmith
• The Girl with the Mermaid Hair by Delia Ephron
• The Girl Who Chased the Moon by Sarah Addison Allen
• The Girl Who Fell from the Sky by Heidi Durrow
• The Girl with Glass Feet by Ali Shaw
• The Girl On Legare Street by Karen White
• The Girl Who Threw Butterflies by Mick Cochrane
• The Girl Who Became a Beatle by Greg Taylor
• The Girl Who Wanted to Dance by Amy Ehrlich
• The Girl In the Steel Corset by Kady Cross

There are a lot more, but I got tired of typing. As you can see, these titles come from books in many different genres, fiction and non-, and marketed to a very broad spectrum of people, some of whom probably haven't even read The Girl With the Dragon Tattoo, or maybe even heard of it.

Why do you think titles that begin with "The Girl Who/In/On/With" are so popular right now? Why do some titles take off like this and others don't, even if the books are just as popular?