Today’s Wall Street Journal article “Technology Boosts Outdoor Ads” addresses the second-fastest growing form of advertising spending behind the internet, outdoor advertising. The article is mainly devoted new technology just being deployed in the London Tube developed by 3M that has allowed them display “glueless [paper] posters” which can be put up and taken down more easily and cheaply.

But behind that story is another one of CBS’s winning bid for the Tube to include 150 digital projectors and 2000 video screens in its stations. When outdoor posters become digital signage, we’re taking the first step towards a world in which all screens, including billboards/posters, are connected internet devices.

This BBC article from last week cites the promise of digital signage, “If you believe some agencies, anything that is currently paper and paste is going to become video.” The potential is not just about just about grabbing attention more than ordinary posters would. But rather, it’s about bringing the benefits of digital advertising found on the desktop web to become an “everywhere web.” Those benefits include tracking metrics, day parting, and location-specific messages. Spencer Kelly writes, “A fast food chain can advertise either breakfast, lunch, or dinner. A newspaper may only want to advertise in the morning, a bar only in the evening.” And then there’s the promise of interactivity; once we have a connected screens, the next logical step is to allow consumers to control and engage with them.

But even the strongest pundits are still singing caution about how soon all of this will happen, however. James Davies of out-of-home communications agency Posterscope has said:

“Everybody cites Minority Report and Blade Runner as the future of out-of-home-advertising, and that’s a big exaggeration. We’re not going to see screens on every single street corner over the next few years, mainly because of costs… these are very expensive forms of technology.”

Indeed, while the technology is becoming available and we can clearly see the potential, it will still take time for adoption on three fronts – consumers, advertisers, and real estate – for this new medium. The agencies and technology vendors pushing this new frontier will have to be patient as it emerges, but it’s very interesting to watch nonetheless.