The XMPP Extensions Editor has received a proposal for a new XEP.
Title: Entity Versioning
Abstract:
A method by which rosters and disco items may be versioned so that servers
will not need to send the entire list if it has not been modified, saving
bandwidth and time during session initialization with minimal state being
stored by the server and client.
URL: http://xmpp.org/extensions/inbox/entityversioning.html
The XMPP Council will decide in the next two weeks whether to accept this
proposal as an official XEP.