Apple’s recently released Mavericks OS X 10.9.4 update fixes an issue where known Wi-Fi networks didn’t automatically reconnect, addresses an problem where the background or Apple logo would appear incorrectly at startup, improves the reliability of waking from sleep, and updates Safari to 7.0.5.
The OS X 10.9.4 update also includes all the security patches included in the recent Security Update 2014-003 for Lion and Mavericks.
I recommend all OS X 10.9 workstations be updated to 10.9.4, and I have begun pushing it out to the Mac workstations running Mavericks that Chicago All Covered supports. For historical purposes, the short lived OS X 10.9.3 update added permission fixes for copying/editing/inspecting files off of SMB file server volume, included “improved reliability of network home directories”, and “improved login speed for users in Active Directory groups”. All of these fixes are included with OS X 10.9.4.