Ask HN: Why does Java continue to dominate?

It seems with Clojure, Groovy and Scala (among others), that Java itself as a language would at least be leveling off. But according to the TIOBE index [1], it is gaining momentum, it seems. Why is this?

[1] http://www.tiobe.com/index.php/content/paperinfo/tpci/index.html

Edit: correct spelling