For classes, I'm still unclear as to why you might even use the thin arrow, lest you're providing a mixin. Thoughts?
Mixins... Can you show me an example?
Times when you need a reference to a canonical function object, like with $.proxy and $.unbind. (CoffeeScript could implement => to set the original function as a property of the bound function)
Added a question on github: https://github.com/jashkenas/coffee-script/issues/1934