Good for them. There is simply no reason to deny homosexuals the right to marriage in a secular society. Although, I do not see any good reason to deny them marriage in the church either, but that should be (and is) up to each religious group.
I do find it interesting that gay marriage is what conservative Christians fight against though. Given the amount of actual problems in the world today, spending resources on such a non-issue is alarming to say the least. Gay marriage hasn't brought anyone to ruin. Poverty, destruction of our livelihood through environmental abuse and disease has.