As home automation starts to pick up steam, the choices of standards grow with names like Insteon, ZigBee, and Z-Wave. ExtremeTech.com has an article on some of the choices that are beginning to replace X10:

Insteon, ZigBee, and Z-Wave. They sound more like comic book characters than wireless home-automation standards. But chances are you'll see products using one or all of them at your home improvement store in the next year or two. Unlike other wireless home-network technologies, such as 802.11, Bluetooth, and UWB, these three are narrowband. Their data rates are in the sub-200-Kbps range, they send only tiny bits of data around the house, and they require very little power.

They continue:

Insteon, ZigBee, and Z-Wave are mesh technologies, meaning that all the devices within a network are equipped with radios and can communicate with each other, rather than just with the controller (the device that serves as central command for the network). Each radio has both a receiver and a transmitter and can act as a repeater, passing on data for other radios out of the controller's range. The radios will be relatively inexpensive, adding $20 or less to the cost of the products or devices they are embedded in, such as thermostats, sprinkler systems, or dishwashers.

Overall, a good article to read if you're looking at your home automation options.

Read The Battle for Your Automated Home: Insteon, ZigBee, and Z-Wave