Samba4 isn't ready for production so I'm stuck with Samba3 but I want GPOs for my Windows 7 clients. Is there a way to implement GPOs or something like it using Samba3 without resorting to manually creating login scripts to set registry settings? I'm guessing using the login scripts is the only way but is there software to automate creating them?
GPOs aren't possible with Samba 3 - they require directory services.
Samba 4 is used in production by quite a few people; it's stable, but it lacks some of the features that Samba 3 has, such as printing support (you can run a separate domain member with Samba 3 on it and a printer though), and it doesn't do DC to DC replication well yet.
I'm in the same boat.. (my appliance, zentyal, does not yet have a version with Samba 4..) this is the closest I can find, but have not tried it yet. http://wiki.samba.org/index.php/Implementing_System_Policies_with_Samba