The PHP team announced the immediate release of the much anticipated PHP 5.3 This version is a major step forward for PHP which introduces namespaces,native closures, late static bindings and optional garbage collection for cyclic references, jump label (g0to). Also a handful of new extensions have been introduced (ext/phar, ext/intl and ext/fileinfo) and Windows support has been greatly improved.
The full list of changes can be consulted in the ChangeLog.
Now we wait and see how long it takes before people start to move production sites to this version. I anticipate that this will take long time because of possible incompatibilities between existing codebase and the new PHP version. However new projects should be started using PHP 5.3