Just as we all expected, Mac OS X 10.5.6 for both workstation and server arrived, and this sixth major update to Mac OS X Leopard improves a lot of features, as well as fixing some problems encountered in previous version. The download is pretty large, with 373MB/668MB for those updating the client software running version 10.5.5/earlier, and 469MB, for those running Mac OS X 10.5.5 Server/earlier, so while you're downloading the file you need, why don't you check the list of enhancements below?
Mac OS X 10.5.6 Enhancements(Client)
Address Book
Improves reliability of Address Book syncing with iPhone and other devices and applications.
AirPort
Improves the reliability of AirPort connections, including improvements when roaming in large wireless networks with an Intel-based Mac.
Client management
Improves reliability of synchronizing files on a portable home directory.
Fixes an issue in Mac OS X 10.5.4 and 10.5.5 in which managed users may not see printers that use the Generic PPD.
Client computers that use UUID-based ByHost preferences now respect managed Screen Saver settings.
iChat
Addresses an issue that could cause an encryption alert to appear in the chat window.
Setting your iChat status to "invisible" via AppleScript no longer logs you out of iChat.
Resolves an issue in which pasting text from a Microsoft Office document could insert an image rather than text.
Graphics
Includes general improvements to gaming performance.
Includes graphics improvements for iChat, Cover Flow, Aperture, and iTunes.
Includes fixes for possible graphics distortion issues with certain ATI graphics cards.
Includes overall performance and reliability fixes.
Improves Connection Doctor accuracy.
Fixes an issue that could cause messages identified as junk to remain in the inbox.
Fixes an issue that could cause Mail to append a character to the file extension of an attachment.
Addresses an issue that could prevent Mail from quitting.
Improves reliability when printing PDF attachments.
MobileMe
Contacts, calendars, and bookmarks on a Mac automatically sync within a minute of the change being made on the computer, another device, or the web at me.com.
Networking
Improves Apple File Service performance, especially when using a home directory hosted on an AFP server. Important: If you are using Mac OS X 10.5.6 (client) to connect to a Mac OS X Server 10.4-based server, it is strongly recommended that you update the server to Mac OS X Server version 10.4.11.
Improves the performance and reliability of TCP connections.
Improves reliability and performance for AT&T 3G cards.
Updates the ssh Terminal command for compatibility with more ssh servers.
Printing
Improves printing for the Adobe CS3 application suite.
Improves printing for USB-based Brother and Canon printers.
Parental Controls
Addresses an issue in which a parentally-controlled account could be unable to access the iTunes Store.
Includes general fixes for time limits.
Resolves an issue that prevented adding allowed websites from Safari via drag and drop.
Time Machine
Fixes issues that could cause Time Machine to state the backup volume could not be found.
Improves Time Machine reliability with Time Capsule.
Safari
Improves compatibility with web proxy servers.
General
Includes Mac OS X security improvements. See this website for more information.
Addresses inaccuracies with Calculator when the Mac OS X language is set to German or Swiss German.
Improves the performance and reliability of Chess.
Improves DVD Player performance and reliability.
Performance improvements for iCal are included.
Fixes an issue when running the New iCal Events Automator action as an applet.
Adds a Trackpad System Preference pane for portable Macs.
Improves compatibility with smart cards such as the U.S. Department of Defense Common Access Card.
Updates time zone data and Daylight Saving Time rules for several countries.
Mac OS X 10.5.6 Server Enhancements
File Services
Improves performance and reliability of Apple File Service.
Spotlight provides more reliable results when remote users search a server volume with Spotlight searching enabled. Important: This change takes effect when you enable Spotlight searching on a sharepoint. In order to take advantage of this improvement on a sharepoint where you have already enabled Spotlight searching, disable Spotlight searching, save, re-enable Spotlight searching, and save again. The sharepoint will remain online during this process, but Spotlight searching will be unavailable for a short time while the index is rebuilt.
Fixes an issue that could make NFS exports unavailable at server startup.
Podcast Producer
Podcast Producer now supports Digest-MD5 authentication, for improved compatibility with Active Directory users, and Kerberos authentication for single sign-on.
Note: In order to use Single-Sign On in Podcast Capture, you must explicitly select that Authentication Type option in Preferences. For more information about enabling Single-Sign On for the Podcast service in an Open Directory environment, click here. For more information about enabling and disabling authentication methods on the server, see this article.
Improves reliability of camera connections.
Password Server
Improves performance of Password Server replication.
System Imaging
When deploying a system image created from a volume, the target computers will no longer have identical local KDC files. For more information, see this article.
Added NetBoot/NetInstall model filters for recent MacBook, MacBook Pro, and MacBook Air computers.
Server Admin
Fixes an issue that could cause Server Admin to stop responding when propagating permissions on a folder which is on a volume other than the boot volume.
System Performance and Reliability
Improves overall system reliability.
Improves performance and reliability of TCP connections.
Fixes an issue that could occur when ejecting a volume on a Promise VTrak RAID.
Improves reliability of RAID Utility.
Addtional improvements
Improves Mac OS X Server Security. For more information about the security content of Mac OS X Server 10.5.6 see this article.
Mac OS X Server 10.5.6 also includes all other improvements delivered in the Mac OS X 10.5.6 Update (client) mentioned above.
At last, it should also be mentioned that security updates for Mac OS X 10.4.11 Client and Server have become available, adding 72MB/133MB(PowerPC Client/Server updates) or 163MB/133MB(Intel Macs Client/Server) to your amount of data to download...
