Fingerbob is a simple Finger daemon which displays formatted user information from an LDAP directory. It is useful when you're in a dark corner of the server room without a GUI and need to find a phone number. Almost every networked computer has a finger client, so Fingerbob provides a simple but universal network address book. It can also provide text documents and list all people in a specified branch of the LDAP directory.
Fljud (the Flexible LDAP Jabber User Directory) is a JUD that uses an LDAP directory for user information. You may find it to be very useful if you already have a Jabber server using LDAP for account authentication and vcards. It can replace your existing JUD, or can be quickly adapted to present and edit other information from your LDAP directory using Jabber.
I think that Netinfo has more in common with LDAP than the Windows Registry. In fact, Apple seem to be emphasising using Netinfo as a gateway to LDAP with Jaguar. I use LDAP with my Linix, FreeBSD and Solaris boxes instead of NIS or /etc files for exactly the same data that Netinfo supplies on a Mac OS X box. It doesn't make them any less "UNIX".
Mac OS X is quite different to typical UNIX in many ways, but not too different.