My girlfriend is a small and normally quiet kind of girl. She'll smile at someone faster than she'll say "HEY YO HOW'S IT GOING?!?!" I like that a lot. Of course, she's less shy around me now, but I still see her as that type of girl. I find it quite cute!
That's the thing though. A lot of men just want some physically attractive woman to have their way at, with no consideration for personality or habits.
But in my case, the classic cute shy girl thing is best!