What is the next big thing in Instant Messaging?
I feel strongly that there will be a boom in XMPP for machine-to-machine natural language communication (AI vs. AI).
Extensible Messaging and Presence Protocol http://en.wikipedia.org/wiki/XMPP
Further, if there were any decent IM-Voice bridge (app) available, then not only would everyman have safer hands-free instant messaging, but would also be able to speak with their own AI using speech i/o.