The official press release of Samba 4 can be found on the Samba website.
In short, you can join a Windows (all recent releases should be supported) machine to a Samba Active Directory, and it will behave much as it does in AD, including Kerberos domain logins where applicable. Samba 4 is now at a point where it can begin replacing existing production deployments, and users are encouraged to try out Samba 4 in a test environment before implementing it in a work environment!
Except for a small number of deprecated features, Samba continues to provide all the features and functionality found in Samba 3.6, and as such is an excellent file server and domain member as well.
General Documentation on Samba
Samba as a Active Directory Domain Controller
Here you can find everything to setup a Samba Active Directory Domain Controller and all that is related to this topic.
- Samba Active Directory HOWTO: Contains everything for setting up a basic Samba Active Directory Controller
- Migrating a Samba 3 PDC to a Samba Active Directory Domain Controller: If you are running a Samba 3 NT4-style environment and want to move to Active Directory, this is the documentation that contains all the necessary information
- Beyond Samba: Connecting other Services/Daemons to your Samba Active Directory (e. g. authentication, etc.)
Samba as a Domain Member Server
- Samba Member Server setup in an Active Directory environment: This HOWTO is based on Samba 4 (Recommended)
- Samba and Active Directory: Samba 3 and AD
Miscellaneous Configuration Topics
Here you'll find all configuration/setup topics that can't be associated directly to an ADC or member server
- v4-0-test (branch for next 4.0.x release)
- v4-0-stable (branch for current 4.0.x release)
- master (current Samba development for future releases)
- For more info on available branches, as well how to obtain the sources via a Git client, see the samba.org devel page.
Historical Documentation on the Development of Samba4
- Franky: A Hybrid Samba Active Directory Controller (outdated!)