Speaking atGDC Taipei (opens in new tab), the director of the last two Final Fantasy games (XIII and XIII-2), Motomu Toriyama said that Square Enix will be avoiding productions like that in the future.
Now, that does not mean that Final Fantasy is dead or that Square Enix will not be releasing big games anymore. Toriyama's exact words, "Within our company, developing on PlayStation for Final Fantasy XIII we required a huge amount of graphical data. … At the peak, there were over 200 people working on it,” he said. “The breakdown there was 180 artists, 30 programmers, and 36 game designers.”
Needless to say, that's a huge team, even for a big-budget modern game. Toriyama said that the enormous team led to big problems with communication and testing.
Toriyama's later comments suggest that Square Enix will focus a bit more on outsourcing in the future. Which is to say that the core experience may be designed and built internally at Square Enix by a small team then the grunt work of actually creating all of the art assets and environments (etc) would be farmed out to an assisting developer.
So while FFXIII-2 obviously isn't Square Enix's swan song, we may see a somewhat different approach taken to the next game in the series. We'll be interested to see how that works out for them.