The truth is that there are lots and lots of hosts that are still on PHP 4. There are still lots and lots of lines of PHP code that make use of PHP4-level features (see Wordpress and Drupal for examples). My complaint is that PHP 4 has been officially unsupported for the last year now, and PHP 5 has been out for over five years. Five years! That’s a long time to wait to take advantage of new features in the language.
Sadly, developing for PHP 4 backwards compatibility is something that companies and individuals are still doing. Wordpress released a new Widget API in version 2.8 that relies on the old-style PHP 4 constructor. Apparently, for Wordpress and many other developers, wide adoption is more important than language improvements.
Changing your coding style is a long process :( Sure my coding style is these days much more PHP5 than a few years ago but I'm still in progress to write powerful OOP based classes for php5 or php6.
At least most hosting provider offering now php5 enabled plans.
Wordpress and PHP4
Yeah really bad I see even in new code parts a lot of old fashioned coding styles :(
I think that some people still provide code written for PHP4