"Back in 2005, the promise of PHP 6 was to be the next big thing for the open source dynamic language. At the time, I remember joking with Zend co-founder Andi Gutmans about Perl 6, which is a release that also has been promised for years and still hasn't been released either.
"Instead what has happened to PHP 6 is it has become the horizon of PHP. A place that you can see off in the distance, but can never be reached.
"It's also a place where features are backported from, as was the case with the PHP 5.3 release which included several key features that were originally intended for PHP 6."