Read the discussion about this on Slashdot: Sites Rejecting Apache 2?.
3. PHP is crippled for commercial reasons The performance of PHP can be increased to 500% by using caching [benchmarks]. So why is caching not build into PHP? Because Zend, the maker of PHP is selling its own Zend Accelerator and of course, they don’t want to cannibalize on there own commercial products. But there is an alternative: APC. 4. No namespaces Suppose someone creates a PHP-module that can read files. One of the functions in this module is called read. And someone else’s module can read web pages and also contains a function read. Then it is impossible to use these modules together because PHP will not know which read function you want. An easy solution to this is namespaces. It was a suggested feature for PHP 5, but unfortunately it didn’t make it. Now, without namespaces, every function has to be prefixed with the module name, to prevent name collisions. This leads to terrible long function names like xsl_xsltprocessor_transform_to_xml which makes code harder to write and r
