The Java runtime shipping in Mac OS X 10.6 Snow Leopard, and Mac OS X 10.5 Leopard, will continue to be supported and maintained through the standard support cycles of those products. 'This means that the Apple-produced runtime will not be maintained at the same level, and may be removed from future versions of Mac OS X. 'As of the release of Java for Mac OS X 10.6 Update 3, the version of Java that is ported by Apple, and that ships with Mac OS X, is deprecated.' The most significant change is documented in the developer release notes. However, those are not the most interesting items about this release. The history of macOS, Apples current Mac operating system formerly named Mac OS X until 2012 and then OS X until 2016, began with the companys project to replace its 'classic' Mac OS.That system, up to and including its final release Mac OS 9, was a direct descendant of the operating system Apple had used in its Macintosh computers since their introduction in 1984.

The general release notes are here and the security fixes are listed here. Apple released Java for Mac OS X 10.6 Update 3 (and a corresponding Java for Mac OS X 10.5 Update 8) through Software Update shortly after the Back to the Mac event.