Use the Termcase module to apply taxonomy formatting

Enabling free-tagging also introduces the problem that every user can change it's own way of formatting the tags. One could use ALL CAPS, or even AnYThinG they like. Once saved in the database, Drupal's auto-suggesting of terms makes sure you cannot change these terms using the node/add or node/edit interface. You have to go to the Vocabulary settings page, find the term and then manually change it once a users enters it in the wrong case.

An example of how it could become after some weeks:

Tags: Music, Cars, animals, food, rock&roll, Drinks, etc

I'm quite a purist when it comes to styling. That's why I decided to write a small module that enables administrators to set the formatting of terms per vocabulary. So that every terms that is added to a vocabulary will be formatted to lowercase, or uppercase. Or - often preferred - the first letter uppercase and the other characters untouched.

The module is called Termcase and it even enables you to transform all existing terms at once. It has a Drupal 6 and a Drupal 7 version. So go check it out!