PHP Woes
uokeke.com
uokeke.com
PHP is where it is because it's easy to install, works fairly well, has a huge/comprehensive built in library, and is usable by many types of people. It also has solid documentation on it's website.
If you're really worried about this, use a framework, or templating engine. Smarty is a relatively lightweight solution for splitting logic from presentation, and also handles caching for you.
I initially wrote the app in C#ASP.NET(2.0) but had trouble getting it to work well on the server with mono(problems with GDI), so I switched to PHP and used it as a learning experience. Perhaps I should have used a more general purpose language, but at the time I was unaware of the limitations of PHP.