What's a godparent?
I didn't refer to my godson as my godson until I heard one of his parents do it first. They asked me to be a baptismal sponsor but didn't use godparenting language at first, so I wasn't sure what name(s) they were giving the relationship. I was glad when, just before the baptism, the baby's mother said to him, "These are your godparents!" It's pretty awkward calling a kid your "baptismal sponsee." Really drains the cute right out of the moment.
My wife grew up Catholic, and in her family it's clear that baptismal sponsors are godparents. It's also understood that it's an honor that goes to aunts and uncles. I don't have godparents but did (and still do) call several of my parents' close friends aunt and uncle; one such couple had an understanding with my parents that in the event of a disaster, neither would leave the other's children orphaned.
Other Protestant friends apply the word "godparent" to this backup-parent role and not to their baptismal sponsors. Still others have close relationships with godparents who fall into neither category.
I find all this quite strange, and my wife and I talk about how, once we have kids, one of the many things we'll have to figure out together is what we're talking about when we talk about godparents.
We Americans have got nothing on the Brits, however. According to the Guardian, godparenting across the pond has devolved into something like professional networking. After reading Kira Cochrane's article on the subject, I feel a lot better about the ambiguity here at home. A godparent takes a special interest in your life, especially your spiritual formation; maybe she or he is also your baptismal sponsor, maybe not. Evidently a culture can do a lot worse than that.