It's funny because it's true: From the NYT article (that Mike's already flagged) about the people behind the Martin Eisenstadt hoax, which fooled a number of media outlets (including us):

Mr. Gorlin, 39, argued that Eisenstadt was no more of a joke than half the bloggers or political commentators on the Internet or television.

Given the constant content demands of cable news and the Internet, it's actually surprisinig this sort of thing doesn't happen more often.

--Jason Zengerle