function setPreferences( $label, $value = 0 )
    {
        // this will only work if the label is one of the valid ones.
        if ( is_array( $label ) )
        {
            foreach ( $label as $l => $v )
            {
                $this->o_catalog( $this->catalogId, 'viewerPreferences', array( $l => $v ) );
            }
        }
        else
        {
            $this->o_catalog( $this->catalogId, 'viewerPreferences', array( $label => $value ) );
        }
    }