In a recent post Cal Evans shares his opinion on why he thinks the Drupal project should fork PHP and what benefits he sees for them in doing it.
Obviously moving the functionality [of Drupal] - not to mention the existing userbase - to a new language would be a herculean task; but what if the new language was just a version of the old. What if Drupal forked PHP and began working on its own version? With that thought in mind, I began to think hard about reasons they would want to do this. Here are the four best I came up with.
Cal list of advantages include an improved development process based on Drupal practices, the creation of a tailor made language they could tweak to just their needs, tighter integration between language and application and, of course, the ability to control the future of the language according to their needs.