Scala's capabilities are not really comparable to OCaml, which doesn't even have traits. JavaScript has many influences beyond Self, and is enough of a mishmash even in its original form to have its own point in the list (at best, a not very similar descendant of self).
Scala's OO features are more like Java's done better. OCaml is this weird object system that is structural most of the time sometimes nominative, and then there is that weird ML module system. Ah...I totally forgot about Moby. [1]
JavaScript has been very successful, and got a whole generation of programmers playing around with prototypes without knowing it.
JavaScript's success has less to do with how good the language is, rather sharing the same fate as successful systems programming languages, by being the only gate to the kingdom.
