The questions and answers on this page have been extracted from the Samba technical mailing list.
Can I use Samba 4 on my production server right now?
No. Samba 4 is still under heavy development. Samba 4 is not due to replace Samba 3 soon. Many of the required core features are present, but the code is still alpha and user tools as well as some core features are still missing.
We do however encourage people to try Samba 4, report bugs and give feedback.
When will Samba 4.0.0 be released?
When it's ready. It's very hard to say when that will be. It depends on a lot of things and people's spare time.
Will Samba 4 eventually have a built-in, full fledged LDAP server?
Yes. While we certainly won't compare ourselves with the standards-based products from other vendors (our aim is to please AD clients first, and hopefully do so while complying with the standards), it will include an LDAPv3 server.
Will it also be possible in the future to extend the server by loading user defined schema's?
Alternatively, is it planned for samba to support storing everything in a third party directory server?
We will not depend on other servers but the aim is to be able to use them if available.