Lightning Returns: Final Fantasy XIII, the third and final(?) chapter of the Final Fantasy XIII saga, came out in Japan last November, and what do you know, it's pretty good. At least Smash Bros. creator Masahiro Sakurai thinks so.
I think at this point, saying Lightning Returns: Final Fantasy XIII is the best installment of the Final Fantasy XIII saga is like saying Revenge of the Sith was the best one of the prequels. Not that FFXIII-2 or even FFXIII are "bad" games – but after the hype and excitement of seeing the first Final Fantasy on the PS3 and having it not measure up, I think the collective disappointment was such that the subsequent games felt more like damage control than their own competent installments of the franchise.