My favorite privacy settings
The main improvement with this code would be your handling of jQuery elements.  You should save them in the object literal like you did with plain elements.

Secondly, you can shorten up your code, using jQuery to pull the radio button value.

Your code might be a bit faster, as it works at a lower abstraction level, but if you do choose to use it, it might be better to abstract it out into a DOM function.

Below is the modified code.

$A.Class.create('private', {
    Name: 'Settings',
    J: {
        save_button:          $('#save_button'),
        cancel_button:        $('#cancel_button')
    },
    init: function () {
        var self = this;
        this.J.save_button.on("click", function () {
            $A.Packet.push({model: self.Name});
        });
        this.J.cancel_button.on("click", function () {
            Page.flip('fave');
        });
    },
    pre: function (packet) {
        packet.h_token = Storage.getRemembered();
        packet.privacy = this.getSaved();
        packet.state = true;
        return packet;
    },
    post: function (packet) {
        Page.flip('fave_custom');
        return packet;
    },
    getSaved: function () {
        return $('input[name=privacy]:checked', '#se_form').val(); 
    }
});

/* Put in a DOM abstraction library

            var form_elements = this.E.se_form.elements,
                send_value = '',
                iterator;
            for (iterator = 0; iterator &lt; form_elements.length; iterator++) {
                if (form_elements[iterator].checked) {
                    send_value = form_elements[iterator].value;
                }
            }
            return send_value;
        }
*/