Pics or it didn't happen.

Couldn't let that slide.
I'm way late to the party, but here's my take.
I have had plenty of gay friends and have hung out them enough to be convinced that Nature and Nurture are at play. The most convincing example for me that some people are born gay involves twin brothers that my son has gone to school with since kindergarten. They just finished 2nd grade. One brother is a complete jock and the other one dresses like a girl, likes to play with dolls and spends the majority of his time playing with girls. He has always been this way and his parents are fine with letting him be who he is. He has always wanted to be a girl. It's interesting that kids in the class will often refer to him as sister or girl. They have no concept of what gay means yet.
I have volunteered at the school a bunch and have spent a lot of time with both brothers. I always believed that some people were born gay, some people become gay for whatever circumstance and some people are just open and like to experiment. What I now realize is, if God creates us in his own image, then how could a child born with the wrong plumbing be evil, sinful, etc. I imagine that later in life this guy will have gender reassignment surgery. That got me thinking. Are we saying that you can only marry legitimately if you fork out the money for gender reassignment surgery? That doesn't make sense.
This pretty much solidified if for me that gay couples should have all the benefits and liabilities that hetero couples get from marriage. The biggest drawback to allowing gay marriage IMO is that it will be a huge windfall for sleazy divorce lawyers. Instant increase in client base.
PS- For those that argue that divorce should be made illegal, the impact of that would be that more people would murder their spouses. People already kill their spouse to avoid having to divorce them; could you imagine what it would be like if you couldn't get a divorce? Marriages go bad unfortunately. I pray that mine never does.