The final downloadable content packs for Final Fantasy XIII-2 have hit Xbox Live Marketplace and PlayStation Network today, just in case you're on-board for more. These final pieces include episodes starring popular character Lightning, and significantly less popular character Snow, along with various costumes.
Lightning's episode ("Requiem of the Goddess") shows the full battle between Lightning and Caius that took place during XIII-2. You should finish the game before playing the Lightning DLC, since it includes spoilers -- but the announcement gives no indication that it will help resolve matters. And seeing as this is explicitly called the final DLC, another game seems likely.
The Snow episode ("Perpetual Battlefield") features Snow fighting in the Coliseum, including a fight with the "Arbiter of Time" who has been watching the events of the game and apparently doing nothing about them. What a lazy time god, right? At any rate, finishing it will unlock Snow as a playable character.
Joining them are two new outfits (White Mage for Serah and Black Mage for Noel), and a "Wondrous Wardrobe" pack with 16 outfits for Mog. Lightning's Story costs $4.99 (400 MSP), Snow's $3.99 ($320 MSP), and the outfit packs are $3 (240 MSP) apiece.