The U.S. Supreme Court today just announced that it would not accept appeals from states fighting to keep gay marriages from happening.
This means that in those states where a Federal Court (or highest State Court) held that the state could not deny marriage equality, their decision stands. 
The Supreme Court gets thousands of appeals, and can decide which cases to accept. By refusing to accept these cases, the court has said that the lower decision stays, and that’s the end of it. There’s no where else to appeal to.
So Indiana, Oklahoma, Utah, Virginia and Wisconsin will have to start allowing gays to get married as soon as possible.
Let’s hope this sends about as clear of a signal as possible to all those other states that are still fighting this. Give up. History is not on your side. Justice has won.
EDIT: Apparently, the court did not take a position on other cases that are similar and pending. I am not sure exactly where they are, but it is likely that the appeals from North Carolina, West Virginia, South Carolina, Wyoming, Kansas and Colorado will also either die because they will be withdrawn or will be similarly decided soon.
That means that the number of states with gay marriage is likely to quickly jump from 19 to 30, for more than half of the country.