There are two main standards for home control: ZigBee, which is actually a ratified standard, and Z-Wave, which was created and is controlled by Zensys. As much as we'd like to give the nod to the standards product, Z-Wave has a lead in the number of vendors making products that support it, including light-switch giant Leviton), and also those products are less expensive than the ZigBee versions.
Both systems are RF (radio-frequency) based, meaning do-it-yourselfers won't have to run control wiring or worry about powerline interference, as they would with X10. And both technologies use mesh communication, meaning as long as a switch or a control unit in your house can communicate with just one other unit, it will work on your network. This is especially important because both ZigBee and Z-Wave use cheap, low-power radios, with a maximum range of only a few dozen feet.
In addition to Leviton, key brand names you'll see in the home-control battle are Intermatic, which will market a $99 start-up kit consisting of a Z-Wave control console and two light switches, and Control4, which makes higher-end products using the ZigBee standard (Control4's basic light switch is $99 by itself). At CES, I also spied a few home-control start-ups, such as Bulogics, which makes a set-top box that can control a Z-Wave installation via a clear TV-based user interface.