public static function get_sites( $blog_ids = false ) {
		if ( !is_array($blog_ids) ) {
			global $wpdb;
			$blog_ids = $wpdb->get_col("SELECT blog_id FROM $wpdb->blogs ORDER BY blog_id ASC");
		}
		$return = array();
		foreach ( $blog_ids as $blog_id ) {
			$return[] = new Site($blog_id);
		}
		return $return;
	}