People failing to grasp the concept
They're not trying to create a third gender, or ruin their son's life - they're giving him more opportunities. The fact that most of you make a distinction between boys and girls sorta sums up why we need to steer away from the gender stereotypes.
Who on earth says that a guy can't wear a dress? That a girl can't play with action figures? There's a biological gender, yes, with distinct differences between guys and girls, but that does not mean that you shouldn't be able to play with Barbies, or wear pink just because you're a guy.