Smarter Transit Routes Through Twitter?

According to Pavlus, besides being artfully rendered, Fischer's visualizations of geotagged tweets, "amount to something close to a desire path on a macro scale: The maps show where our buses and subways should be, if they conformed to the way we actually move and live."

Although the stark black and white maps certainly reflect some structure of the city, without a more detailed explanation of the methodology involved in their creation, it's still unclear what the direct correlation is to transit.