A nice enhancement would be to extend this to support multiple languages, each with its own recognisable formatting.
This could be implemented by adding a drop-down list of languages next to the "dialog" button so that when "dialog" is pressed, it inserts the selected language tag. I.e., if the poster were to select "Common" from the drop-down list of 20 languages and then press the "Dialog" button, the feature would insert the tags into the post.
When the post is subsequently rendered, each different language would have its own, different formatting style.
I.e., the Common tongue might be bold+blue style, Elvish might be italic+autumngreen, Goblintalk might be bold+olivegreen, and so on.
For bonus points, the game referee would be able to configure the available languages and the formatting style of each language in his particular game

Thoughts?