Something else that has happened recently is the announcement by Facebook that they're using MQTT in their new Facebook Messenger app They've posted some details in a facebook-engineering blogpost and cite the low bandwidth and battery usage as important considerations.
This is very exciting as an application that is potentially huge and very user oriented (rather than "internet of things" oriented), but the really exciting bit is if you use an iPhone under Settings and Licenses (apparently it's quite hard to find):
Thanks to Michael Rowe for getting me the screenshot and Andy Piper for pestering Michael on my behalf.
You should note that if you're in the UK, the Facebook Messenger app isn't currently available.