sex will always sell.
its just a fact with marketing. if the item is made for men, or the people the item is being sold to is mostly men, then who wouldn;t use a beautiful woman.
and if women are going to be the target audience in the near future, then use a muscular good looking man or something. it will still work. even though women still have more common sense than guys, they are still human and have a sex drive.
sex just plays on some of our baser instincts and, as i said in the SC sexist thread, sex=pleasure pleasure=good good=buybuybuybuy