I've said it before and I'll say it again, FFXIII is going to underperform what many peoples expectations are. Many peoples (online) expectations are for it to 'revive the series' and 'sell 6-8 million units'. Whereas its probably going to sell similar to FFXII or even less.
And a good example is this thread. People are not interested in a game that's just looking to be a repeat of all the past FF games with a new coat of paint or yet another Final Fantasy game promising 'amazing graphics you will never believe'...that pretty much comes down to 30 hours of FMVs and dialogue and 10-15 hours of boring repetitive gameplay.
I know many FF fans will probably tear me to pieces for saying these things, but overall, some people have to admit. Every other game or so, the FF series pretty much focuses on either STORY AND GRAPHICS or trying to deliver a complete package with gameplay included. This one is shaping up to be one of those 'story and graphics' ones, like FFVII. The series needs more titles like FFVI, VIII and FFX, where gameplay and customization were a factor.
Six upcoming games you should look into:
Essay Pro