I have to disagree wholeheartedly with the OP. Like it was already mentioned before in the thread, she sounds strong in her feminine role. A welcomed change for female characters in JRPGs that are in central leading roles.
The voice acting in FF XIII is rather good from what I've seen (heard?) so far. The female antagonist is also spot on.
Only Sahz (is that name final?) sounds a bit off to me. His voice actor has too strong a tone for the character's funny looking facial expressions.

The only way to know the actual quality of Japanese VA is to be fluent in Japanese.  I think Lightening's English VA is superb.  We must have watched different trailers.

I know, lol! How could anybody watch that trailer and NOT like Lightning's VA!?

This is the quote of the thread (and very good reasoning in the next post). I could not agree more. The sad thing is they have no idea wtf the character is actually saying, and not only that, the Japenese VA seems to be far more exaggerated than what a person would normally sound like in the same situation.

omg... Zen.... Stop making her sound so badass!

I have never had a problem with voice actors in Final Fantasy, but I do prefer Japanese audio for the most part because they seem to be much more into it and convincing for the most part. But english audio done right is fine.

Also, I would not say I know "good" japanese voice actors, but for the most part they make scenes seem more intense because they actually get into and aren't afraid to yell and stuff in front of a michrophone.

english dubs are usually the worst ones. latin dubs also suck during the roman empire.

I thought Lightnings voice was awesome personally. Strong and well suited.

I'm still pissed about "Stereotypical Black Guy." I thought after FFVII we wouldn't have to deal with that shit again.