Obviously I'll applaud when a powerful international institution moves in the right direction, but I really roll my eyes at the "same-sex marriage is fine as long as we don't call it marriage" thing we've been hearing for years. Plenty of self-described liberals were there about 7 years or so ago. Even now I frequently hear the sort of mirror argument - why is the state involved in marriage at all! just call them all civil unions! - which is equally dumb.
I mean, I don't care what we call it. We can call it "pancake" if that will make people happy. If churches don't want to add their ritual to some state contract signing ceremonies that's perfectly fine. But the idea that there's something magical about the word "marriage" is just silly.