Gay Marriage, I believe is unacceptable in an open society.
Marriage should be between a man and a wife, solely because man and a wife play a different role in a child's life. While mother plays the role of a nurturer, the father, when older plays the role of a role model and a friend.
It is obvious that two men raising the child is not as adequate as a man and a woman raising that child. No matter how feminine one of the male may be, men all share one trait that is always there, promiscuouity. Why? because men can impregnate many while women can only do it once.
But how would these parental differences affect the child's development? What is the adequate raising of a child?