Like everyone else has said, I don't think there is one specific reason. The name is just a popular choice because it could stand for a number of different meaningful names. It's a nice fallback name. Something logical. And while I admit that occassionally I see it in a story and think, "Again?" I'd MUCH rather see them use one of the stand-bys (CJ, Lara, Jon, etc) than some ultra-trendy name with a creative spelling. Lois and Clark are upper-class professionals - The chances of them naming their children Rhylie or Tyffanie is slim to none. I'm super sensitive to this sort of thing after spending years studying the sociologic factors that go into what names parents choose for their children, but I know I'm not the only one who is jolted out of a story when Lois and Clark name their children something like that.
Annie
