In regards to your last point. I dont see the homosexual marriage thing anywhere near the interracial thing. Regardless of race they were still heterosexual. Homosexual marriages cannot say that.
Set up the legal framework for gay couples, dont call it marriage. Marriage is a religious connotation. Call it whatever the heck you want but dont call it marriage. In that vein, states should get out of the business of issuing marriage licenses and instead issue a document showing legality of the "contract" Let the churches issue the marriage papers.
And thanks for the South Park ping!
Finally, another sensible person. The states getting out of the marriage business would put an end to all of this.