Women's feelings on preferring men hairy or not are largely tied to their own experiences.
For instance, a girl grows up with a hairy father she liked and respected a lot, and she views hairy men as more masculine. Or, a girl has an amazing boyfriend who had a shaved / hairless chest, and she views hairless chests as most attractive now.
Personally, I sport a relatively hairy chest, and I LOVE getting complaints about it early into relationships. Girls will tell me, "You're so HAIRY!" or, "I think you'd look even better if you shaved your chest and stomach hair."
To this I respond, "Tell you what. When I decide I want to look like a BOY, I'll shave my chest. But for now, I want to look like a MAN, so I'm just going to leave this right here."
What invariably happens is, after a few months of great sex and great experiences, you'll find yourself lying there in bed naked with the girl, and she'll be playing with your chest hair telling you, "You know, when we first got together I didn't really like your chest hair. But now I'm SO GLAD you have it... it's SO MANLY."
Of course, if I didn't grow chest hair, and a woman complained about my lack of ventral keratin strands, I'd simply tell her that when I decide I want to look like a bathmat, I'll grow chest hair; until then, I'm going to stay smooth, accented, and defined, like a professional body builder.
It's all the simple anchoring of emotions - if she has great experiences with you, she'll anchor that to things about you that stand out to her. There was a study on smell that found that women who reported good sex with their partners were found to love their man's smell, while women who reported bad sex were repulsed by smelling their man. In my experience, this extends to all kinds of things - from your gut to scars you have to birth marks to chest hair.
Give her good sex, and whatever your physical points of differentiation from most men, she'll come to associate them with sexiness and manliness after a couple of months of being with you.
You can effectively retrain women's taste in men this way (and the effect goes both ways - if your first great girlfriend and lover is a certain ethnicity or has certain physical features, you can come to view women similar to her as your "type").
It's fascinating stuff.
Chase