Strongly disagree. When there's an element of mystery there, it's a hell of a lot more intriguing to me. This is also true of the best crime fiction. And when something isn't known well, it's more "rewarding" (for lack of a better word) when you manage to hunt it down. (I've had a blast over the past year searching for Youngstown stuff, because it's a lot harder to find.)

On a somewhat related note, another thing I like is when stupid myths about the mob get shot down by people who know what they're talking about.