Ilia Alshanetsky, the release manager for the PHP 5.2.x series has officially announced the release of the latest Release Candidate for the series - PHP 5.2.0RC6.
The 5.2.0 release is turning to be quite an adventure, we can't seem to get the bloody thing out. Hopefully RC6 will be the last release candidate, but given that I've said that about the last 3RCs, who knows...
You can grab the release snapshots from his section of the Downloads on PHP.net (with Win32 binaries to follow soon). So, grab it, test it, find those bugs, and help the PHP team get this next big upgrade out the door!
UPDATE: the Windows binaries have been posted by Edin now.