[wp-hackers] Javascript bind event for 3.5's new uploader?

[Luke Bryan]

Greetings,

In previous versions of Wordpress, it was fairly simple to add
Javascript on a hook for the iframe of the upload/media gallery.
Currently, 3.5 uses a much faster Backbone.js, and templating in
wp-includes/media-template.php, instead of iframe.

I'm trying to add an action when the uploader is displayed, but I
can't seem to call the .on or .bind from external code. The relevant
caller is in media-views.js:1965-1983:
        open: function() {
            var $el = this.$el,
            options = this.options;

            if ($el.is(':visible'))
                return this;

            if (!this.views.attached)
                this.attach();

            // If the `freeze` option is set, record the window's
scroll position.
            if (options.freeze) {
                this._freeze = {
                    scrollTop: $(window).scrollTop()
                };
            }

            $el.show().focus();
            return this.propagate('open');
        },

When I break on the last line, then enter at the console
"this.on('open',function(){alert('hi')});" it works. Code will be run
whenever the dialog opens.
Unfortunately, it seems this can't be added from external code.
wp.media.editor.on, wp.media.editor.bind, and others will not work.

Best regards
Luke