Drush script to read NIDs from a CSV file and bulk delete the nodes using node_delete()

node_bulk_delete_by_nids.drush.php

<?php
/*

This is a 'drush php-script' alternative to the SITE.com/devel/php approach 
to this answer - http://drupal.stackexchange.com/a/81221/4450

A short description of drush php-script below
$ drush help php-script
Runs the given php script(s) after a full Drupal bootstrap.

Example of how to run this script
drush php-script /path/to/this/file/node_bulk_delete_by_nids.drush.php /path/to/csv_file_with_nids.csv
^ Make sure to run this command from within the desired drupal site's directory tree

*/

$path_to_file = drush_shift();
$nids = file_get_contents($path_to_file); 
$nids = explode(",", $nids); // This will depend on how your nids are delimited. Could be line break "\n"
foreach ($nids as $n) {
  node_delete($n);
}