After a very long and exhausting development process that's been going on since 2003, while simultaneously developing the Samba 3.x series, Samba 4.0 is dancing closer to an official release this year.
Several Samba developers working towards the 4.0 release were on-site talking about the long-awaited 4.0 release, Microsoft's support of Samba and their annual engineering get-together in Redmond, and other topics related to this open-source project for integrating with various Microsoft Windows services.
Development on Samba 4.0, which is a major rewrite, began in 2003 with their first technical preview arriving in 2006. Since then the 20-year-old free software project has seen 17 alpha releases of Samba 4.0, with the last alpha release coming just before Oktoberfest.
The last piece of the Samba 4.0 puzzle the developers have been working on is integrating the Samba 3 file-server into the Samba 4 server code-base. When that's done, they will hopefully be ready for release, but it will be brought up for public discussion. They say the Active Directory portions of Samba 4.0 are ready to be used. The Samba developers have learned a lot from their annual meet-up with Microsoft where they have hacking sessions for a week.
Among the features of Samba 4.0 are support for Active Directory logon/administration protocols, a proper test suite, an internal LDAP server, an internal Kerberos server, Bind9 integration, fully a-synchronous internal design, better scalability, a new RPC infrastructure, Python support, a generic security sub-system, and many other enhancements. More details on the Samba 4.0 state and features can be found from the Samba.org Wiki.
There is no release date set for Samba 4.0, but based upon the sounds of it, 2012 should hopefully be the year that sees this significant feature release. Embedded below is the full Samba 4.0 talk from Linux.Conf.Au 2012.