Here in Chicago, we have the "L", a vast network of elevated trains that runs throughout downtown, to the neighborhoods of the south side, west side, north side and even to a few near suburbs. Businesses are positioned all along the tracks, some directly underneath. Combined with all of the bus routes, the Chicago Transit Authority (CTA) expects 458.2 million rides in 2006. Increasingly, those riders are carrying mobile devices that allow access to the internet - and shopping.
I'm no mathmetician, but 458.2 million rides seems like an incredible opportunity for businesses to reach a captive audience through their mobile devices. A Scarborough Research study found that mass transit users and "power pedestrians" (consumers who walk three or more miles in a city over the course of a week) make up about 22% of consumers in the 75 US markets surveyed. The study also found that subway riders are 27% more likely than other consumers to have spent $2,500 or more on Internet purchases in the past year.
Services such as Yahoo Local Advertising offer many options to advertise locally to your target audience. Combined with the proximity that commuters are to any number of retail locations during their daily rides, it could be a great opportunity to grab an "on-the-go" audience. It's a powerful incentive to stay abreast of mobile search marketing strategies, especially for those local businesses with brick-and-mortar locations along busy commuter routes.