This should be interesting. It’s almost certain to be a 5-4 decision no matter which way the court decides.
In effect, this will legalize same-sex marriage in all 50 states, but it will require gays in states like Oklahoma to travel out-of-state to have the ceremony performed; Oklahoma will then have to recognize their marriage when they return. This will permit Kennedy to both legalize same-sex marriage everywhere while still saying that he hasn't abandoned states' rights.