By AppleInsider Staff

Published: 05:00 PM EST

Apple Inc. this week is believed to have wrapped up development of Mac OS X 10.5 Leopard while simultaneously pushing out yet another pre-release copy of its final maintenance and security update for Mac OS X 10.4 Tiger users.

Mac OS X 10.5 Leopard

A source tells AppleInsider that Mac OS X 10.5 Leopard is now "finalized" to the point where Apple has begun to provide Leopard-related support training materials to its support staff.

Among these initial training materials were self-paced training modules on some of the operating system's most popular features and components, such as installation methods, Mail and BootCamp.

The last full pre-release of Leopard arrived on September 21st, when Apple provided its vast developer community with Mac OS X Leopard build 9A559 in what was then assumed to be a release candidate.

A week later the company released a small automatic software update for build 9A559 but did not increase or otherwise change the Leopard build number as it had done in previous cases. Therefore, build 9A559 is the last known candidate that could be declared Gold Master and released to manufacturing.

All signs have pointed to a public release of Leopard during the business week of Oct 22nd, with sources specifically singling out Oct 26 for the official launch.

Update: MacRumors notes that Apple may have yet to declare a build of Leopard Gold Master despite what it may be doing to prep its employees for launch. Internal builds are reportedly "still progressing" with more definitive word on a GM build expected in a few days.

Mac OS X 10.4.11

Meanwhile, AppleInsider has also heard that Apple on Tuesday pumped out two new builds of Mac OS X 10.4.11 -- widely expected to be the final update to the Mac OS X 10.4 Tiger operating system.

The new builds -- 8S161 (for PowerPC Macs) and 8S2161 (for Intel Macs) -- focus primarily on Dashboard, according to some of the people testing the releases. This reportedly includes a fix for the software's underlying Webkit foundation and word of two existing issues with number-oriented widgets.

Mac OS X 10.4.11 is now set to deliver over four dozen minor bug fixes and code corrections to users of Mac OS X Tiger.