handle the submit button
You're trying to assign a value to an object property without declaring the object.  Try this:

function review_m_admin_settings_form_submit($form, &amp;$form_state){
    $node = new stdClass();


There's actually not any need to check if $node->text isset either because we know we haven't set it already. 

You also need to pull your form values from the $form_state variable.  For example:

$node-&gt;text = $form_state['values']['text']