I also see a problem in the current shift in technology we see from websites in document form to full-features webapplications (HTML5, JS). Google is pushing this shift, too. But search robots still don't execute JS. Therefore it is not easy to develop a modern webapplication for users with good UIs and at the same time optimize for search robots.
In general I would say the more experience in programming you gain the less it matters what language you are using. Learn the basics first. And learn language types like OOP and functional programming. As a professional web developer you should try to learn several frameworks as well (Zend Framework, RoR, Django, etc.). But I would say that's the second step and not the most important one. Frameworks and API come and go, they change all the time. Try to get the big picture.
I'm currently using PHP and Python. I like Python more because of it's simple style and it's clean APIs. But still most of my professional projects are done in PHP because my customers want it that way.