In a new note from the main PHP site:

The third (and hopefully final) Release Candidate of PHP 5 is now available! This mostly bug fix release improves PHP 5's stability and irons out some of the remaining issues before PHP 5 can be deemed release quality. Everyone is now encouraged to start playing with it!

There are few changes changes since Release Candidate 2, which can be found here.

It's getting closer and closer, and while most of the changes in this release are just smaller bug fixes, it brings up one big step closer to the final release. So, get on over and download it today - and get testing!