I wish I had the ability to write it but sadly, no. However, I am all about getting as much info to the people that can. The API for the Rachio is publicly available online at the following link. Maybe this will help persuade someone to tackle this.
+1 for the plugin.
btw is there instructions on how to write a vera plugin? if i have free time over some weekend i might give it a try (if no one has done it yet)
Edit: found it: http://www.mios.com/developers/become-a-mios-developer/
Did you ever do this?
Sorry just saw your msg now. Fortunately I never had time to pull it off.