1. A method of identifying ad-spots within geo-referenced imagery by utilizing sign-ness characteristics of portions of an image frame that depict suitable advertisement locations, the method comprising: providing an image database containing actual imagery captured from at least one camera traversed along a physical route, the actual imagery having a generally horizontally oriented perspective; storing the sign-ness characteristics in a database as discrete data structures containing one or more information fields relating to the suitable advertisement locations; creating records for image portions that exhibit detectable unique sign-ness; extracting image portions depicting suitable ad-spots from image frames having an appreciable level of sign-ness; categorizing image frames with an unappreciable level of sign-ness as background imagery; processing image frames containing an appreciable level of sign-ness, such that the suitable advertisement locations are categorized as road signs or potential advertisements; and identifying a region of an image frame containing a potential advertisement and assigning a unique identifier to the region, wherein multiple successive image frames containing the region comprises an ad-spot.