Not this is news if you’ve been paying attention (it’s all over PHP.net) but it’s out.
Release Candidates pave the way to an official release (as in “to the best of knowledge, this is stable or with documented bugs”). In other words PHP5 is close.
Nows the time to get your say in. Download the release and test it. See how your existing code handles it. Find bugs bearing in mind the changes and the PHP4 > 5 Migration Guide, and report them (while remembering to read how to report a bug).
Particularily important, no doubt, will be feedback from Windows users. Although PHP is cross platform much of the core development is done on Linux (I assume) so issues on Windows often turn up later. If you don’t want disappointment when a stable release of PHP5 hits the streets, add your input.