You can now grab OS X 10.5.5 from Software Update.
What does it have? From http://support.apple.com/kb/HT2405:
- Includes recent Apple security updates.
- Addresses stability issues with video playback, processor core idling, and remote disc sharing for MacBook Air.
- Addresses an issue in which some Macs could unexpectedly power on at the same time each day.
- Resolves a stability issue in TextEdit that could be found when accessing the color palette.
- Improves Spotlight indexing performance.
- Fixes an issue in which contacts might not sync properly with PalmOS-based devices.
- Improves iPhone sync reliability with iCal and Address Book.
- Includes improvements to Active Directory (see this article for more information).
- Improves Speech Dictionary.
- Fixes Kerberos authentication issues for Mac OS X 10.5 clients that connect to certain Samba servers, such as Mac OS X Server version 10.4.
- Includes extensive graphics enhancements.
- Addresses stability issues that may occur when creating a Smart Group.
- Resolves a printing issue with address cards containing information that spans more than one page.
Disk Utility and Directory Utility
- Improves reliability when rebuilding a software mirror RAID volume in Disk Utility.
- Improves reliability of server status displayed in Directory Utility.
- Updates iCal to more accurately handle repeating events.
- Improves performance when choosing meeting attendees.
- Resolves an issue in which the “Refresh All” option may be dimmed (“grayed out”) in the contextual menu for certain calendars.
- Fixes issues with read-only calendars.
- Addresses an issue that prevents an invitee from moving an event to a different calendar.
- Resolves an issue with syncing published calendars.
- Addresses performance issues related to displaying IMAP messages.
- Resolves an issue with SMTP settings for AIM, Compuserve, Hanmail, Yahoo!, and Time Warner Road Runner email accounts.
- Addresses stability issues that may occur when dragging a file to the Mail icon in the Dock.
- Addresses an issue with the “Organized by Thread” view in which the date does not appear when the thread is collapsed.
- Resolves an issue in which RSS feeds could temporarily disappear from the sidebar.
- Improves Mail robustness when sending messages.
- Improves reliability when saving drafts that have attachments.
- Improves overall sync reliability.
- Improves Back to My Mac reliability.
- Improves Time Machine reliability with Time Capsule.
- Addresses performance issues that may affect initial and in-progress backups.
- Fixes an issue in which an incorrect alert message could appear stating that a backup volume does not have enough free space.
- Time Machine can now back up iPhone backups that are on your Mac, as well as other items in (~/Library/Application Support).