I loved FFXII. I didn't really like X, or any of the Nomura influenced Square-Enix games, so seeing something different made me feel good.
I thought the battle system was great. I don't really get to play MMOs, so having a nice and similar one-player game made me happy. The Gambit System felt great since you didn't have the other people to control the other characters. I also liked the License Board system a little better than the Sphere Grid b, and it's a shame that they have no plans to use it for XIII. The Liscence Board felt a little constrained and linear. If your character was a White Mage, and you wanted him have something else, you had to turn him into a White Mage, then a Breaker, then a Black Mage, etc. unless you had a key too break out of that loop. With the License Board you just had to follow a general area to become that type of class. I haven't played X in a while so I could be wrong.
The only problem I had with the battle system was that it wasn't wacky enough. The game could've used more effective commands other than attacking, and some more skills like Bubble and Oil. I don't think I've used a single negative status effect on an enemy other than Oil. Perpetual Moogle mentioned this once in another thread, but Final Fantasy X's status effects were extremely hard-hitting. I actually liked X's battle systems, but I would like to see those same effects put into a game like XII. It felt like all I was really doing was attacking and healing.
I enjoyed the story to XII. It felt like a nice change of pace from the other FF stories, especially X. Usually in those games the stories are over-the-top and anime influenced. I don't really watch anime, and I don't understand why ALL of the Final Fantasy games have to be anime styled. They got rid of the melodrama, the plot-twists, the end of the world/existence plot for a nice realistic one. The characters didn't have these ridiculously long backstories or these extreme amounts of character development either. They acted like people who could exist in our world. XII also had a set theme and a lot of allusions to the war in the Middle East today. XII would've made a really nice book, and that's a compliment you can't give to most JRPGs.
I do kinda agree with what angry black man was saying. The story was way to tame. Compared to a lot of other game stories it was nice, but compared to the other Matsuno games it was shit. They could've gone more in-depth with the effects of war on a country. It also would've been nice to have seen Rozzaria and to have them affect the storyline. There should've been more political backstabbings and horrible topics in the game like racism and famine like the other Matsuno games had. Those games actually felt medieval and gruesome. Tactics had its characaters stabbing each other left and right. Vagrant Story had a villian who ripped another man's skin off. I loved the Tactics Advance setting being blown up into a full world, but the game would've been much better off with a darker and deeper storyline.