Apple has reportedly [1] seeded another build of Mac OS X 10.4.9, labelled "8P2120".

This build fixes several bugs identified in former builds while its "known issues" list has shrunk to zero.

Last week, Apple had also released a new build labelled "8P2117" bringing several fixes.

Accelerated build releases and the fact that there is no known bug on the latest build may indicate that Apple is readying to release this update which will certainly be the last being made available Mac OS X Tiger.

Mac OS X Leopard is scheduled to be released this Spring, as mentioned by Steve Jobs several times. The information was re-iterated by Apple management during Apple' Q1 financial release.