There's not much that has changed about the basic workings of the power grid since AC power beat out DC as the standard at the beginning of the 20th century. Power plants dump electricity on a network of power lines, homes and businesses pull energy off the lines. The energy supply needs to closely match demand so there are guys who monitor both to make sure the right power plants are making the right amount of energy at the correct time. There's not much that's "smart" about the system, but it works and it's what we've been doing for a long time. It's also, in it's dumbness, fairly immune to internet hacker style attacks.
One of the buzzy concepts in green energy is the idea of the smart grid- a connected network of homes, businesses, and other buildings that pull electricity off the grid through monitors that connects back up with each other and central servers. Power plant operators can better see energy loads and consumers can track their energy use (and typically, reduce it). Both sides win when consumers use expensive appliances during off-peak time when power is cheaper, saving the utility companies the expense of having to bring on fast response generators.
But one of the biggest potential hurdles with the smart grid is security. While a network of connected devices monitor and controlling energy use will be a great boon in the drive to cut energy waste, it's also an incredibly tempting target for hackers, super villains, and other various bad guy types. Whatever technology gets built has has to come with reliable, rock solid security features.