stock_picking_delivery_users_view.xml

<?xml version="1.0" encoding="utf-8"?>
<openerp>
    <data>

        <record model="ir.ui.view" id="view_stock_picking_delivery_form">
            <field name="name">stock.picking.delivery.form</field>
            <field name="model">stock.picking</field>
            <field name="inherit_id" ref="stock.view_picking_out_form"/>
            <field name="arch" type="xml">
                <data>

                    <xpath expr="//form[@string='Delivery Orders']/group/group/field[@name='backorder_id']" position="after">
                        <field name="user_id" invisible="True"/>
                    </xpath>

                    <xpath expr="//notebook/page[@string='Products']" position="after">
                        <page string="Assignment">
                            <field name="user_ids" nolabel="1" on_change="on_change_user_ids(user_ids)"/>
                        </page>
                    </xpath>

                </data>
            </field>
        </record>

        <record model="ir.ui.view" id="view_stock_picking_delivery_tree">
            <field name="name">stock.picking.delivery.tree</field>
            <field name="model">stock.picking</field>
            <field name="inherit_id" ref="stock.view_picking_out_tree"/>
            <field name="arch" type="xml">
                <field name="state" position="before">
                    <field name="user_id"/>
                </field>
            </field>
        </record>

        <record model="ir.ui.view" id="view_stock_picking_delivery_calendar">
            <field name="name">stock.picking.delivery.calendar</field>
            <field name="model">stock.picking</field>
            <field name="inherit_id" ref="stock.stock_picking_calendar"/>
            <field name="arch" type="xml">
                <data>
                    <xpath expr="//calendar[@string='Calendar View']" position="replace">
		        <calendar string="Calendar View" date_start="min_date" date_stop="max_date" color="user_id">
                            <field name="origin"/>
                            <field name="partner_id"/>
                        </calendar>
                    </xpath>
                </data>
            </field>
        </record>

    </data>
</openerp>