You probably know about the Tiobe software index.
But does website volume really tell how popular a language is? I bring you charts of languages by job listings.

Here are the functional languges. As you can see here, F# is starting to grow. But Erlang still surpasses all of them by far.

These are the so called heavy weight, industrial languages. Java is sitting at the top while C# is closing in. C++ remains steady. We see here that Cobol is still surviving all these years.

And here are the interpreted languages. Interestingly, Javascript is number 1 while Perl is close behind.
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Interesting stuff.. one thing that jumped out at me is the popularity of JavaScript, even though you have it categorized under “moderately used languages”. In fact, its popularity almost exactly matches C#:
http://www.indeed.com/jobtrends?q=javascript%2C+c%23&l=
java 4 life