It's the sort of error that strikes fear in every editor. Glad it wasn't me, etc etc. Leaving out that one little letter transforms an otherwise unremarkable word into a career lowlight. A public embarrassment to be trotted out over drinks — later. (Never happened to you? Count your blessings.) For as the editor of the Clay,W.Va.weekly the Communicator says, among readers: "Some laughed, some didn't."
Worth noting here that spell check would not have helped, since the "wrong" word is still a word. So let's be careful out there — otherwise the errorists win.