What's hot in scripting languages

Scripting languages are becoming more serious. Higher levels of abstraction mean more little languages, better-adapted to specific purposes. Dismissing scripting languages as 'unserious', which some developers still do, is like criticizing mammals for beating out sauropods: specialization does multiply types, but each type becomes (or can become) way more efficient at its particular job. And for many web applications, plenty of jobs can be focused pretty tightly.

(Maybe the clearest demonstration of the kind of abstraction I mean is the difference between CoffeeScript and JavaScript syntax.)

But which scripting languages are on the rise, and which are waiting (or beginning) to die? The fact is, there is a lot of overlap among existing scripting options. And for the developer with a deadline -- often an especially serious issue for web applications --  a language's familiarity can easily become more important than its suitability. But familiarity can direct a deadline-driven developer dangerously close to dinosaurism.

Peter Wayner from InfoWorld offers his own take on which scripting languages are hot right now, and why.

Wayner pays a lot of attention to O'Reilly sales, at least as a measure of a language's popularity (if not suitability). He doesn't really address Dart, Google's attempt to replace JavaScript altogether. But even if JavaScript will eventually lose its hold on client-side scripting languages, it certainly isn't going to happen overnight (or overweek, or overyear..).

Good issues to keep in mind, I think.