LGBT: What do you think of the role of Gay Marriage interacting with the human evolutionary process?

I don't care about the marriage issue just because marriage is so diluted now anyways. But what influence will Gay platonic families have on the future of man? Could everyone become Gay giving rise to surrogate mothers, sperm donation and test tube babies being the main form of reproduction? Its a riddle, + = reproduction of our species, what happens as we slowly move away from this?