Hmmm... The last thing I heard was that they wanted to delay it into 2008 because they wanted more PS3's in the market. It was more or less a rumour from what I recall.
Snooping around google, there has never actually been a definitive release date set by Square. That being said, they are probably just working extremely hard on it so they have another FF3/7/10 caliber game.
By life end:
- Wii- 100 million+
- Xbox360- 35~40 million
- PS3- 30 million
- PSP- 30~32 million ------------- FAILURE
- NDS- 85~90 million (Skeptical) - FAILURE
- NDS- 100 million+ (Optimistic) -- Success!