social/mass_mailing_statistic_extra/views/mass_mailing.xml

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

<record model="ir.ui.view" id="view_mail_mail_statistics_tree">
    <field name="name">Mail statistics extra columns</field>
    <field name="model">mail.mail.statistics</field>
    <field name="inherit_id" ref="mass_mailing.view_mail_mail_statistics_tree"/>
    <field name="arch" type="xml">
        <field name="mail_mail_id_int" position="attributes">
            <attribute name="invisible">1</attribute>
        </field>
        <field name="message_id" position="attributes">
            <attribute name="invisible">1</attribute>
        </field>
        <field name="message_id" position="after">
            <field name="subject"/>
            <field name="email_from"/>
            <field name="email_to"/>
        </field>
    </field>
</record>

<record model="ir.ui.view" id="view_mail_mail_statistics_form">
    <field name="name">Mail statistics extra info</field>
    <field name="model">mail.mail.statistics</field>
    <field name="inherit_id" ref="mass_mailing.view_mail_mail_statistics_form"/>
    <field name="arch" type="xml">
        <field name="message_id" position="after">
            <field name="subject"/>
            <field name="email_from"/>
            <field name="email_to"/>
        </field>
    </field>
</record>


</data>
</openerp>