Duke Energy recently opened a $1Million facility in Erlanger, KY in order to demonstrate Smart Grid concepts. The following story contains a good description of smart grid (except for being a bit heavy on the consumer side, that is it should also mention what SG can do for the grid itself, going back to the substation and beyond):  

   "Smart-Grid is a term for a network of sophisticated sensors, distributed computers and other black-box communications devices installed on a utility's existing network of wires, poles and transformers to remotely monitor power delivery in much greater detail than today. 

      It has capabilities as mundane as automated meter reading and remote service connection, and as sophisticated as remote monitoring and control of customers' energy use - and the size of their bills. "

 Source: http://news.cincinnati.com/article/20081012/BIZ01/810120457 

Hopefully, Duke will also demonstrate how its smart grid will integrate intermittent renewables like wind and solar into network operations, and do so in real-time.