When I was pregnant with my first DC, I didn't think about whether I had a preference for either a boy or girl, I was just overjoyed to be expecting a baby full stop. DH was the same, or so I thought, and if anyone asked it was all 'as long as its healthy' blah blah.
A few months after DS was born, DH admitted that he was longing for a son and would have been disappointed if he had been a girl. It shocked me really and got me thinking whether all men would prefer a son, whether they admit it or not?