I don't think it's quite there, yet. Everything's in place, and Elixir is a wonderful language, but it hasn't been quite battle tested yet.
On the other hand, Erlang is pretty ubiquitous behind-the-scenes, and I wouldn't be surprised if some enterprises do develop their internal software in it.
On the third hand, since Elixir uses Erlang's runtime, it'll be subject to less required battletesting for the same reasons that JVM-based languages (like Clojure, Groovy, Scala, and JRuby) are quickly gaining popularity in enterprise environments that already use Java.
> JVM-based languages (like Clojure, Groovy, Scala, and JRuby) are quickly gaining popularity in enterprise environments that already use Java
They are. Though of the 4 examples you gave, only Scala's really being used to build systems, though Clojure's being used by some who don't mind forgoing static typing. Groovy's a scripting language used for short test and build files, and for Grails. I don't think JRuby ever got used much in production.
You might be right about Groovy. I've seen JRuby used pretty heavily in enterprise environments, though (usually to integrate Rails with an existing Java-based system).
On the other hand, Erlang is pretty ubiquitous behind-the-scenes, and I wouldn't be surprised if some enterprises do develop their internal software in it.
On the third hand, since Elixir uses Erlang's runtime, it'll be subject to less required battletesting for the same reasons that JVM-based languages (like Clojure, Groovy, Scala, and JRuby) are quickly gaining popularity in enterprise environments that already use Java.