[Samba] The Big Plunge

[Sorisio,Chris]

Hola folks,

After a few years of slowly phasing in various Linux and BSD platforms, the
company I work for is willing to take a hard look at replacing its existing
Windows NT domain controllers with a Linux/Samba combination.  We only have
about sixty people in our main office, but most of my experience is with
smaller deployments.

I'm not looking for step-by-step instructions, that's obviously my
responsibility to figure out. ;) 

I'm looking for success stories - those of you who have successfully
migrated a Windows NT domain to Samba, and how you've benefitted from the
move.  

General questions I do have:

1.  Will a Samba PDC establish trust relationships with NT PDCs?
2.  What anti-virus software exists for Windows clients which will
automatically grab signature updates from an internal server?
3.  Do you mostly use scripts to manage users, or a GUI?
4.  Is it LDAP/Samba integration possible?

Thanks,

Chris