The easiest way I found to get wifi working is through the shell.

• SSH to the system. (futurebit:futurebit)
• run 'sudo armbian-config'
• go to Network->wlan0->
• If you tried to configure through the web interface, select "Forget" (otherwise continue to WiFi)
• select WiFi, and activate your wifi network here
• once connected, cancel out.

Once you reboot without ethernet plugged in, it should come up on WiFi.