XEP-0084, (PEP-based) User Avatars, is in Last Call. We should consider implementing it, with vCard-avatar backwards compatibility, much like the way we support both PEP-based and legacy nicknames.
It looks reasonably simple to implement. A metadata PEP node (to which we're meant to subscribe) pushes out metadata updates, which replace the SHA-1 seen in presence; a data PEP node (to which we're *not* meant to subscribe) contains the avatar itself, replacing the vCard.
I implemented XEP-0084 and it seems to work with my contacts that use Conversations*.
* Note: Conversations publishes avatars in the webp-format and your gtk/gdk installation may miss the decoder. A solution is available here: https://github.com/aruiz/webp-pixbuf-loader
(In reply to Ferdinand Stehle from comment #1)
> I implemented XEP-0084 and it seems to work with my contacts that use
Thanks for working on this!