The OpenId authenticator and provider already works
pretty well based
in the current not very clean authentication api with some hack
because Markus did not had choice to do this otherwise. I just did not
had time to integrate it yet in the trunk but Raffaello Pelagalli
started do to some test with it to integrate between
http://l10n.xwiki.org and
xwiki.org farms (l10n is on its own instance
of XWiki).
See
http://jira.xwiki.org/jira/browse/XWIKI-2630 ,
http://jira.xwiki.org/jira/browse/XWIKI-2588 and
http://jira.xwiki.org/jira/browse/XSALBATROSS-34
Right. The implementation is complete but I guess the tests are still
missing (kind of difficult to write meaningful tests for it).
The implementation supports both, RP and server. XWiki can accept OpenIDs
from other sites as well as issue OpenIDs to be used on other sites
supporting OpenID. That way you can use your XWiki account all over the web
(well at least on sites that support OpenID).