What this confirms: 1) Lightning has no no-shield setup. 2) The way Lightning is posed indicates that all weapon/shield combinations will likely use the same animations. There might be variation on animation speed I guess.
Otherwise, there's nothing interesting to discuss. We already know regardless of what kind of weapon she equips, her offense-type stats (just these 2: Power (whatever they call physical strength), Magic) will change. The shield governs HP, ATB recovery, and possibly buffs/debuffs.
What you can consider the most interesting aspect is that you can attach buffs to the abilities, so when you use an ability the passive buff might activate.
Lightning actually has a shield in that picture (blue thing). The evidence for no shield is 1. The cloud costume and 2. gauntlets as an item, which share a slot with the shield.
We've seen her spell cast animations with the staff, and they do use a different animation than her sword spell casts.
Since she does have a shield in that picture, I'm guessing that's just her "neutral" stance. I don't think it's out of the question for all of her weapons to have different attack animations, at least. A spear surfaced in one of the videos posted today (I had a link several pages back; I'll go find it when I have time) and I can't imagine Lightning swinging it around like she does with a sword.
These all lead me to believe her weapons will certainly have different attack animations.
My hope is that the different animations will lead to different gameplay styles. That is, spear animations have a longer reach but less horizontal area, for example. I'm skeptical that this will happen since the game is first and foremost appealing to the RPG crowd, but hopefully more is shown soon.
Where did you hear about the buffs activating on passive abilities? Sounds like a good way to consolidate support spells and attack spells. Perhaps related to the spell combo system?