The protocol is from 2008. None of the carriers were getting around to supporting it (since it's federates to AT&T and Verizon have to have their own servers that talk to each other), so Google is publishing a "universal profile" so Android can talk to Android at least. This is really just Google kicking the carriers kicking and screaming into 2010 level technology. As a standalone protocol, it's not great. As an upgrade to SMS it's long overdue.
