What is a dandy?

So if you haven't heard, it's that time again: The New Yorker is holding their 2008 Eustace Tilley Contest. Tilley, drawn by Rea Irvin (also responsible for the headline type) in 1925, has been famously rendered by the likes of Chris Ware, Robert Crumb, William Wegman, and others. The deadline for submissions is January 24th, and you can check out the competition here. In 2005, Louis Menand wrote about Tilley's evolution and eventual deconstruction.

New Yorker readers have become used to him, but it's not much clearer eighty years later what he's supposed to represent. Beginning in 1994, efforts were made to do something to his image, which seems, after all, to have little connection to New York City. (Irvin derived it from an 1834 drawing of a Count D'Orsay, "man of Fashion in Early Victorian Period," that he found reproduced in the costume section of the Encyclopædia Britannica.)

Hmm...If mental_floss were to have a Eustace Tilley, I'm trying to imagine what he would look like. He'd certainly surpass the cloying smarm-and-brimstone of Pocket Change's Richard Nouveau. But here's my primary question: it's great that The New Yorker at once solicits and sends up their target demo in Tilley, but all I want to know is (& since we've covered the vicissitudes of nerd-dom to death): what, really, is a dandy after all?