While this keyart isn’t 100% new, this quality is. It was previously posted by Famitsu, however Square-Enix Japan has officially released it! Enjoy.
You can check out the Japanese website here (Which also received an update today, opening up the Prologue area)! Remember, there will be a special TV airing on Japanese TV on the 15th, as well as Tokyo Game Show starting that same day with Final Fantasy XIII-2 very much present at the event!
Credit to miladesn on Twitter for the find.
Edit: The site also added a new wallpaper featuring the main Serah and Lightning keyart! Along with this, they also added Valhalla under Fields, some other new wallpaper, and Lightning to the characters list. Check them out at the link above!