i havent talked specifically about guy pubes with my friends but i know some girls like guys who are a little high maintenence and keep their legs shaved and clean looking while other girls think its gay for a guy to shave his legs. some girls are grossed out when they see a guy's happy trail but i know other girls that think its sexy. i dont know about most girls prefering that a guy trim his hair. maybe in the younger teen girl crowd because when you're younger, older guys are more intimidating.
my opinion is that male genitals are equally strange looking shaved or unshaved. i think if a guy is comfortable with me enough to sleep with me, he should be comfortable enough to not worry that i'll be grossed out if he doesnt shave. and if i didnt shave already, i would be insulted if a guy told me to because if i'm sleeping with him, he should think i'm beautiful no matter what.
a little off topic but i also want to say that i think its gross when guys dont shave their face. most teen guys can't pull it off because the rest of your face looks young and the hair is so thin and in uneven patches that it just looks dirty and lazy and rediculous.