I think CAROLS is an excellent song, just like Over and Close to you are excellent as well.
At the first times I listened to CAROLS I thought it was really good, a week after I was finding the song terribly annoying specially because of the bridge (go figure why). A week later though I was loving the song back again. I sang to it several times while I was driving (not as much as I did with Moments though, almost anytime I would get in the car I would sing that song).