Idea for a short film

[KurtNYC]

Is this a decent idea?

Using a digital video camera and a shotgun mic, tape people while they talk on their cell phones in public. Cut the footage together so it looks like they are talking to each other. The conversation grows as they put one call on hold to take another. The locations people are talking in become more and more problematic -- the top of subway stairs, bookstores, stepping off the curb against the light (in front of a bus). Possibly show split screens (ala "Pillowtalk") with many waiting on hold. The climax of the film depicts the entire island of Manhattan coming to a standstill as every person in the city is on the phone.