A rumor, which was that Final Fantasy XIII will be released during 2008 in Japan. But Nomura only said that the developing team hopes to release an battle system demo of the game during 2008. Because of these rumours Square Enix has released the following announcement.

"Although information regarding the release date of FINAL FANTASY XIII has been reported by certain videogame websites, Square Enix itself has yet to make an official statement on this topic. Any reports of a confirmed release date are erroneous and should be disregarded.

Square Enix will make an official announcement in the future concerning the release date when it has been determined."

Source: Game Anime Hybrid