I don't think it should be legal.
I know there are many of my friends that disagree with my view on this.
However, that does not mean I will change my view at all.
I believe that the true reason Sodom & Gomorrah were destroyed was because gay marriage was "legalized" and/or "sanctioned" by the government. Taking away the true meaning of marriage: a contract between Man and Woman, ordained by God almighty. Or in other words - only entered into under church authority.
I have no problem with you having opposing beliefs, but just note that I think any other op pinion on this matter is wrong.
I believe this is a total black and white issue. No gray areas. I think it is morally, ethically, and overwhelmingly wrong.