It appears that neither are going to release before the end of this fiscal year (March 31, 2008). GameStop's website recently moved MGS4 from a 2007 release to a March 2008 release, but chances are it'll come out in April or May. Just because ... it'd be a good start to the next fiscal year, you know?
FFXIII hasn't been moved on their site, but Square Enix president Yoichi Wada made a statement regarding the game at a financial briefing in Tokyo: "It will still take a bit more time. At the very least, [a release] this fiscal year is definitely out of the question." IGN claims a May 2008 release at the earliest. We second that. When do you guys expect the game to get the ol' release?