With so many different options, this has been a fun service to use. You can set up events based upon detecting motion with a camera or time when you want lights turned on and off. You can set the temperature of your house remotely - if you forget to set it back when you've gone on vacation. You can also monitor your energy usage and see things like what time of day you use the most energy.
I installed most items myself - except the thermostat and the energy reader. Those should probably be done by a professional.