I recieved my Chocobo after a fair bit of hassle in early 2010. Here’s what the prop looks like in use by a Sazh look-alike:
Sazh’s costume can be bought from the marketplace for 320 MSP here
I’m afraid eBay is the only way to go for these Chocobos now. They were not part of the selection of Final Fantasy XIII avatar items added to the marketplace.
The old article:
As a way to promote Twitter on Xbox 360, Microsoft have provided a free avatar item for Final Fantasy XIII. They asked the community to tweet and tweet on the subject until… a Chocobo was revealed.
All the tweeting has been done so now all you need to do is visit the necessary webpage click Register Now and fill in all the necessary gumpf. The items will be sent out mid-December.
Here’s a preview of what you might get: