I am curious. How did they shut off your air conditioner without shutting off the power for rest of the house?
They attach a device to your air conditioner. I had it at my old house. My air was never shut off (that I noticed0.
Smart Meters inherently have the capability to control any smart appliances in your house. Whirlpool and GE will have washer/dryer units and hot water heaters on the market this year. The system is two way - they send your consumption data and the system at the client end receives commands to control the smart appliances. One utility has boasted of being able to control over 200 electrical devices at a single home. It is expected that smart appliances will be mandated over the next 3-4 years.
See http://epic.org/privacy/smartgrid/smartgrid.html
They have to install a load switch on your air conditioner. The load switch is controlled by the meter, which gets a signal from the power utility to being "shedding" (technical term) loads. Your specific house is not targeted. Usually, it's a particular area in the utility's grid.