As announced on the main PHP.net site, several new versions of the language have been released including one for the upcoming PHP 7.3.x series:
The v7.1 and v7.2 releases are bugfix releases and include changes in core functionality, date handling, FTP, Tidy and XML.
The PHP 7.3.0RC5 release is the latest Release Candidate for the PHP 7.3.x series. If all goes well and no major issues come up, the next step in the release process is to officially branch the 7.3.0 release and have one more Release Candidate (6) before a GA release.
As always you can download the bugfix releases from the downloads section (or windows.php.net) and the Release Candidate from the QA site (or windows.php.net/qa). Bugs found should be reported via the PHP bug tracking system.