[16th ave.]

i wouldn't go with the nail polish thing, but there's nothing wrong with a good pedicure for men and women. if the son is wanting nail polish then he is most likely exploring how he feels about such things and generally just going through the motions figuring out who he is and would like to be. figuring out who you are as person and want to be isn't something that just happens over night or any any really specific age. its like when kids are little and they get asked what they'd like to be when they grow up. the nail polish does not have to mean something about the child's partner preferences later on. it could be leading up to the child maybe wanting to be a make up artist or something along those lines.
either way, i wouldn't be too concerned with it. he is your son. being a parent generally means accepting him no matter what he does.