There is a new version of Server for 10.9 that you will need to purchase and/or download thru the App Store. Workgroup Manager is available as a separate download:
I have also been running the Server version all summer, and it includes a newer version of the Caching Server, which will cache iOS, iOS Apps, OS X (10.8.4 and above) updates, App Store content, and iTunes content for your network, with no client configuration required. You just need to have the Server on the same WAN connection as your clients. This is huge way to save bandwidth.
jason
Jason Hyerstay
Network Manager, ACTC
Waterbury-Duxbury School District
I installed Mavericks on a test machine this morning. If you are running Mac os 10.8 servers, you will not be able to run Workgroup Manager, or the Server utility. The servers will also have to be upgraded or you'll have to use a 10.8 client machine to run the software. I haven't had time to play with it yet. The first thing I'll test is to make sure it connects properly with our current LDAP solution which I'm sure it will.
Bryan