One thing to watch for here is what I hereby dub the "Reverse Cocktail Party Effect". Recall that one stubborn response to instances in which Justice O'Connor or Justice Kennedy strayed from the conservative line in individual rights cases has been that they just want to keep getting invited to Washington cocktail parties. In this vein, keep your eyes peeled for enlightened right-leaning legal thinkers expressing support for equal marriage rights but furrowing their brows at application of the rational basis test to denial of those rights.
*Other than abject laziness, of course.