The use of literally in a fashion that is hyperbolic or metaphoric is not new—evidence of this use dates back to 1769. Its inclusion in a dictionary isn't new either; the entry for literally in our 1909 unabridged dictionary states that the word is “often used hyperbolically; as, he literally flew.” We (and all the other “craven dictionary editors”) have included this definition for a very simple reason: a lot of people use it this way, and our entries are based on evidence of use. Furthermore, the fact that so many people are writing angry letters serves as a sort of secondhand evidence, as they would hardly be complaining about this usage if it had not become common.
