I would like to suggest using Google Wave as a networking solution for smart houses.
Google Wave offers instant communications and the posibilty of simple scripting. As it is hosted from a server, it can be accessed from anywhere with internet access.
Your house would have it's own wave address. Each item you own would have one as well. Just add the item to a wave and it would streamline the networking. For example, if you are at work, your house temperature may be 80 degrees. Your system know that it takes 12 minutes to bring the temperature to 70. When you are on your way home, your smartphone Waves your house that you are 12 minutes from home (using GPS, speed and road reports). Your home is perfect when you get there.
If you are not familar with this up and coming technology, a developer preview can be seen at: