In this video tutorial we'll cover how to upgrade from Drupal 7.23 to Drupal 7.24. It's pretty painless, but there's a few tricks to it.
For more reading Detailed info on upgrading between major Drupal versions — https://drupal.org/node/1494290
Why you should upgrade to 7.24 — https://drupal.org/drupal-7.24-release-notes
A soul crushing amount of detail on version 7.24 — https://drupal.org/SA-CORE-2013-003