Well the hacking is definitely the most potentially interesting thing here which is why I find it strange that a city would want to open up its services like that to potential attacks. Maybe the promise of Utopia will never end.
I remember with some of the old home gas meters, you used to be able to take off the meter and stick it on backwards and it would run the usage down. People would do this in the middle of the month so by the time your meter was read, it was as close to zero as you could make it. Like the RAND corporations NY computer model, that stopped fire protection in the 60's, you could maybe amp up service in other ways - perhaps trick the city into better water pressure or something. Or even with that iPhone app, about bumpy roads - you could pay a kid $5 an hour to pogo stick with your iPhone in his pocket and have the smoothest commute in town.