Thanks Kyle for posting the links, I've been busy trying out the chip and haven't taken time to follow-up.
My early impressions is that LUA is probably the easiest way to go, I could flash the LUA F/W yesterday and that seems quite versatile, more than the official AT command set.
LUA simulates a filesystem on the flash, and allows to store scripts, with a special script that runs upon boot. If you couple this with an external MCU that handles sensors &actuators, it can make a very low-cost/low footprint IoT device.
LUA support is provided by NodeMCU, links to GitHub at
http://nodemcu.com/index_en.html. I used their flasher which so far has been the most reliable for me, quite neat UI, which also generates a set of MAC addresses, and their flashcodes (not sure what that would be for, tough...).
Another way would be to port the MQTT client C code, maybe extend the AT command set, i.e. AT+MQTTSUB="topic" AT+MQTTPUB="topic",len,payload, incoming subs would come the same way as incoming IP traffic, they currently have a +IPD output, could have a +MQTTD on the same principle.
For a summary of H/W and some S/W links, you may want to check this wiki out too:
http://hackerspace.pbworks.com/w/page/88183850/ESP8266PhG.