Final Fantasy XIII-2 comes out today in North America, but it's already benefiting from simultaneous DLC releases with Japan. Due on Feb. 7, upcoming DLC lets players fight FFXIII protagonist Lightning, accompanied by Lt. Amoda. If you defeat her, she can join your party.
Siliconera reports that future DLC following this Lightning battle will include a costume pack and new story content (which Square Enix says will "enhance the experience and complement the narrative of FINAL FANTASY XIII-2 with storyline branches for key characters in the story," with another coliseum battle coming in mid-March. That wacky Ezio costume will be in there somewhere, as well.