Apple has released an update for OS X Server, bringing it to version 10.1.1. OS X Server is a file server for Web developers using OS X. The update includes improved Apple file services and other enhancements. According to Apple:
Apple is pleased to announce the v10.1.1 update for Mac OS X Server. This update delivers improved improved reliability and performance of Apple file services, Apache web and Mail services under heavy load. Enhancements have also been made to improve server administration, SMB printer sharing, WINS registration and system clock accuracy.
You can find more information about the OS X Server update at the Apple Web site. OS X Server 10.1.1 is availble for US$499.00.