The switches can only be controlled via the app (which is pretty crap) but I have captured and dissected the communication and discovered it is essentially just a UDP packet controlling the switch state. I was considering writing an openHab binding for it; but decided to open up the switch instead.
Home depot product page: http://www.homedepot.com/p/Grounded-Indoor-Wi-Fi-Adapter-2-Pack-CT-065W/206177754;jsessionid=31776537145CBE2EDAF2A319018BFF47
They are also sold under the name Wood WiOn: http://amzn.to/1R9e9Xx
Here is the new firmware I wrote for it:
Update: If you want to try this yourself; John has written an excellent write up filling in many of the steps omitted below; definitely worth a look.
Here is my teardown and programming video: