The common complaint about Lightning in the Final Fantasy XIII series was that she was a boring, stiff character. Well, I don't know what the developers did about the first problem, but they certainly addressed the second problem.
The Square Enix team working on Lightning Returns: Final Fantasy XIII talked openly and candidly about some of the new changes to the game. I'm not going to just pull some quotes and paste them because the context would be completely lost, so thankfully Dualshockers managed to nab the good parts from a Famitsu report that was covering the Premium Event being held in Tokyo, Japan, where designers Nobuhiro Goto, Masaru Suzuki and game director Motomu Toriyama discussed Lightning's boob enhancements:
Q: Is it true you said you wanted Lightning-san’s size from a C cup to a D cup?
Nobuhiro Goto (Character Modeling Designer): Toriyama-san said “I want it bigger” so…
Motomu Toriyama (Director): [What a] cop-out! (laughs)
Goto: Yes, it was enlarged.
Q: Was it a C cup until now? Does it even jiggle this time?
Toriyama: it’s determined by clothing, like the so-called corrective underwear. (laughs)
Masaru Suzuki (Designer): There’s an unreleased costume that exposes the l’Cie scar on her chest. Please think [carefully], is there any other information that should be disclosed? (laughs)
Q: So there were costumes that were rejected?
Goto: I think there are a few designs that were rejected.
Suzuki: If reproducing the outfit proves to be difficult, then I’ll consult with the artwork designer as much as possible, but if the costume design slows down to a crawl, it gets scrapped.
DualShockers also captured another comment from Goto, who mentioned in a Dengeki Online post that...
Yes, her chest jiggles. Since everyone can decide what costume she’ll wear, you can make sure it does (laughs). By the way, Since Lightning swings her arm when you change her weapon in the menu screen, that’s a recommended action for sure-fire jiggling! To see it even better it could be useful to equip a small shield. Look forward to it!
Hmm, I guess it's a bit disconcerting that it's such a huge issue that they discuss it as if it were an obvious change. To be honest, had no one said anything I don't think I ever would have noticed, unless of course videos emerged where the differences were made apparent.
Given Lightning's small build and thin frame, when she puts on the armor you can't really see the differences at all. Then again, I didn't really like Final Fantasy XIII, I never bothered with XIII-2 and none of the characters were appealing enough to pay attention to the synthetic upgrade in Lightning Returns.
Anyway, the change was obviously made to lure in the Dead or Alive fans and the Mai Shinranui aficionados. For the people who were turned off with the first two games, I doubt the physical enhancement to Lightning will pull them back in, especially when some of the bigger complaints were over the convoluted storyline and poor character development, and that's not to mention all the complaints about the actual gameplay.
Lightning Returns focuses a lot more on environmental scaling and exploration, almost identical to the Assassin's Creed games, and the combat and RPG mechanics have almost been completely overhauled to suit a new kind of gameplay.