When Observable is declared with a type (especially an array) it sets up some wrapped methods to simplify working with it.

The wrappers also set up automatic dependency resolution so you can do cool things like:

    list = Observable []

    reversed = Observable ->
      list.map reverse

    list.push 'blah'

    reversed() # => ['halb']

There's no polling, the observable notifies all observers immediately when the value changes.