I don't know if anyone have created a thread for this one.
If not, here you go.

This article is a bit old. But incase anyone want to know this.

I read an article about Final Fantasy XIII cancelled DLC written by Square Portal
I read this on twitter, here's the link to their tweet Final Fantasy XIII DLC that never happened
For the article here's the link Final Fantasy XIII DLC that never happened by Square Portal

The article also includes video and screenshots.

Maybe Square Enix should continue their work on this DLC and make it available for PC, PS3 and Xbox 360. I really hope that