I hated the crappy MMO style battle system in FFXII. In fact, I hate MMO's, not because of the concept, but because of the fetch quests, grind, and the bland battle systems. Never got into FFXII at all because it was like the worst of both worlds. IMHO of course....
I thought this trailer was incredible, and the battle system looked really fun, like it was returning to the roots of classic JRPG's with a lot modern updates. I'm an SNES/PSX RPG junkie, so from what I saw, it was just what I wanted.
I predict another great FF, and we are due. In the modern era, we've had 7, then 10, so 13 fits the pattern. (This is not to say that 8 or 9 were not good, just not to the caliber of 7 or 10, again imho)