According to AppleInsider, OS 10.5 Leopard’s is now “finalized” to the point where Apple has begun to provide Leopard-related support training materials to its support staff.
When it comes to the release date:

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.

AppleInsider also confirms the fact Apple will release a last update for Tiger (10.4.11):

The new builds 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.

Read full article from AppleInsider

Posted in Leopard, Mac OS X, Rumors