Lion Server: GUI, GUI, gone
Other services that appear to be missing in Lion Server are actually still there. NFS (the Unix-based file sharing protocol) is gone from Server Admin, but it is accessible via the command line. Podcast Producer, Mac OS X Server's podcast workflow system, still uses NFS, and you can create NFS-based home folders for users. But where before you could click check boxes to configure it, you now need to type Unix commands. Similarly, the FTP server isn't available in Server or Server Admin but is available through the command line.
If you're looking for the configuration for MySQL, you won't find it, either in the GUI or in the command line. That's because Apple has replaced it with PostgreSQL, another open source database. On one hand, this is an improvement, because PostgreSQL is considered to be more powerful than MySQL. But whereas Snow Leopard's Server Admin tool had GUI settings for MySQL, PostgreSQL is command line only in Lion Server.
With others services, GUI administration tools survived -- barely. Lion Server still has industrial-strength Apache Web services, but it has replaced several windows' worth of settings with little more than an on/off switch and a button to add another host website path and domain name. This makes it more difficult to host multiple websites as virtual hosts or at least more difficult to figure out why it isn't working.
The admin tools no longer provide a way to set URL aliases and redirects, which point to files or folders while keeping the location hidden from uses. Also eliminated is the ability to set domain-name-level Web alias. And the GUI tools provide no way to configure the execution of CGI scripts on a website. You can no longer set maximum simultaneous connections, connection timeouts, or persistent connections. These and other configurations were available in the Server Admin tool in previous incarnations of Mac OS X Server. Rather than simplify Web configuration, this puts much of Apache's features out of reach to those less adept in editing config files.
The same is true for VPN configuration, iChat (Jabber) service, and to a lesser degree the iCal calendaring service.
The exception to all this is email service, which still has the same level of configuration detail as in previous versions of Mac OS X Server, and with a better Web mail implementation.
Lion Server's Profile Manager: The sole bright spot
For business and education, Profile Manager is the shining spot in Lion Server. Once you turn on services and switch on Profile Manager, it automatically creates configuration profiles, which are XML files that can be pushed to Mac and iOS clients that automatically configure them to receive the service. You can send out an enrollment profile, which enables changes to be pushed out (when the user accepts it). You can have different sets of profiles that apply to groups of users, as well as to individual devices and groups of devices.
Profile Manager goes well beyond simply configuring clients for networking, VPN, and mail. You can set hundreds of group policies. For example, you can prevent iOS and Mac users from accessing the App Store, prevent Mac and iOS applications from launching, block users from making changes to system preferences, block Macs from accessing external storage devices or optical discs, prevent iOS users from watching YouTube, set parental controls, and much more. (Users can see the settings applied to their Mac in the new Profiles system preference, or in the familiar Settings app in iOS.)