[giulianob]

Actually just about every popular library out there for JS creates some sort of fake OO layer on top of JS (e.g. Backbone, jQuery, Prototype, YUI, etc..). If you are just throwing a couple of scripts together then JS is fine but if you are trying to make an actual application, you need libraries to make it more OO.

I've worked on large code bases in several languages and JS has to got to be one of the worst when it comes to code quality due to the flexibility. It's always an awful experience trying to refactor a large portion of JS since it's difficult to even find where objects are being used. I'd take AS3 over JS anytime of the day since it allows me to specify types (though optional) and if I do the tooling is able to do a lot of the static analysis that is important in large projects. TypeScript still gives you plain old JS while allowing you to specify some extra information in order to facilitate development. It's actually new developers that aren't aware of these things and love JS from what I've seen. They haven't worked on large code bases and love the flexibility of JS. When you actually are trying to create proper abstractions in order to architect your code, you need visibility modifiers, you need interfaces, and you need types.