I'm finishing the implementation of contacts e2e encryption. This has been done in the context of the serverless metadata reduction grant (https://nlnet.nl/project/ServerlessXMPP/). As the name implies, it let you encrypt metadata on your contacts (name, groups, description), but can also be used to extend roster metadata.
On other fronts, we have talked about sealed sender at last summit (notably @daniel) and @mathieui made a great suggestion about onion routing in XMPP.
@daniel @mathieui This is highly experimental, and the spec/and implementation will probably change a lot with time and feedbacks.
Sealed sender/XMPP onion routing will probably take a (very) long time to come.
But I believe that we are on the right path.
All that is possible because of the extensibility of XMPP. If I had to choose a protocol today to start from scratch again, I'm pretty sure that I would still go the XMPP way.
Stay tuned for the rest of the work on the grant.
Goffi