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"So whats the language I should use then?"
If you don't have your own server at your disposal, then there's no denying that the widespread availability of a language is a compelling reason to use it. For better or worse, network effects have driven me to hypocritically use PHP simply because it's popular with clients.
My own personal projects are more geared towards system programming. But if I were to choose a new web language to learn today it'd be Opa. It seems to be a very welcome radical shift away from the multi-tier approach of SQL/PHP/HTML/CSS/JAVSCRIPT/DOM into a new more convergent paradigm. Not that I can recommend something I have zero experience with it, but I'm never the less extremely interested in what it potentially offers.
My interest in Opa was sparked here on OSNews, actually: