This question comes from the logs. So, let's answer this one nice and quickly:
Guys prefer girls who present youthfulness. I won't go so far as to say guys prefer certain physical traits, because even those physical traits that men track should be seen as a subset of "signs of youthfulness". For me, as an example, a playful chick gets a lot of play from me. I like energy in a woman. I like joie de vivre.
Every woman constantly makes the mistake of thinking that a guy who isn't engaging her is not doing so for what are, quite frankly, feminine reasons. Women play coy with men and they, frankly, like men that play back. Men don't care for that shit at all. The men who do it do so because it works, not because they would prefer to do things that way.
Go to a club sometime and see which girls get the guys. Look at high school kids and see which girls get the guys. The guys aren't buying "feminine mystery".
One of the biiiiig shortcomings women have in understanding the world is a complete inability to construct empathy from anything except their own experiences. Women don't spend much time actually thinking about what life would be like for a guy. Far less, I promise you, than men spend thinking about what life would be like for a girl. Consequently, women make incredibly stoopid leaps of logic in trying to understand men. Such as thinking that since women like mystery, men must like it too.