They better not get too excited. The Mormon's had the same issue with polygamy with the same fight under the protection of religious freedom, however, federal/state law still prevailed.
Very few states have sexual orientation as a protected class. So I'm honestly not sure what exactly this law does that wasn't allowed before?
I don't support it, but it seems like a bunch of law makers putting into legislature something that was already allowed anyway.
Below was a statement President Clinton made after DOMA was signed into effect in 1996, President Clinton has since come out and said he disagrees with this law. But, you are correct in the sense most states do not have sexual orientation specifically protected in their discriminatory laws.
President's statement on DOMA
Statement by President Bill Clinton
On Friday, September 20, prior to signing the Defense of Marriage Act, President Clinton released the following statement:
Throughout my life I have strenuously opposed discrimination of any kind, including discrimination against gay and lesbian Americans. I am signing into law H.R. 3396, a bill relating to same-gender marriage, but it is important to note what this legislation does and does not do.
I have long opposed governmental recognition of same-gender marriages and this legislation is consistent with that position. The Act confirms the right of each state to determine its own policy with respect to same gender marriage and clarifies for purposes of federal law the operative meaning of the terms "marriage" and "spouse".
This legislation does not reach beyond those two provisions.
It has no effect on any current federal, state or local anti-discrimination law and does not constrain the right of Congress or any state or locality to enact anti-discrimination laws. I therefore would take this opportunity to urge Congress to pass the Employment Non-Discrimination Act, an act which would extend employment discrimination protections to gays and lesbians in the workplace. This year the Senate considered this legislation contemporaneously with the Act I sign today and failed to pass it by a single vote. I hope that in its next Session Congress will pass it expeditiously.
I also want to make clear to all that the enactment of this legislation should not, despite the fierce and at times divisive rhetoric surrounding it, be understood to provide an excuse for discrimination, violence or intimidation against any person on the basis of sexual orientation. Discrimination, violence and intimidation for that reason, as well as others, violate the principle of equal protection under the law and have no place in American society.