If you want to develop website with PHP you should note some point regarding PHP. 1) For Dynamic and intractive website PHP is always the best option available. 2) Be it Drupal, Joomla, Magento, Wordpress, all the open source CMS works well with PHP. 3) Whatever operating system you may have, PHP is supported in All of them - linux, xindows, etc. 4) It runs well almost all the server be it Microsoft Internet Information, Apache etc. 5) Very easy to debug. I would like to be contradicted on this note.
This is because you are used to it. ASP / JSP is also used and are by no means less than PHP but PHP is mostly preferred because of it seamless into *nix environment. They do not work well with PHP but they work in PHP. One of the main reason for its popularity but again it should not be used with Windows on Live sites because you can run into many problems and one of them in use of redirect rules. Again this depends on your expertise in the language.
Ok, shabbir has a point, but why is your post title is Why hire PHP programmer? and you answer is like: how cool is PHP!
