I got it opening day and have played it solid for about 2 days and here are my thoughts.
First off, the game is VERY linear. Its not like FF7 where you get dumped onto a world map to explore. This game is linear in how you start at one end of a straight line essentially and work your way through the level to the end and a cutscene. That might be good or bad, personally I dont mind it a bit.
One thing I have to give props to though is the way the game doesnt dump everything on you at one time like previous games. It has tutorials and the AI takes most of the control (like picking parties and leaders, etc) till you progress further then gives you more control little by little. Some may not like that but I think its genius. I get overwhelmed with these games from the start and this cures that.
The fighting is still turn based like RPG's usually are but you wont sit there and click "fight" over and over mindlessly like some older games. This one you have to switch formations that in turn change each characters role. In one formation, or paradigms as they are called, a character may be a fighter but in another paradigm the same character may be a healer. And you have to switch around through out the fight for many reasons. In other words its not near as mindless and there is a tecnique to it. Very cool.
Farming/grinding isnt as needed as it is in previous FF's. You get to spots (and the strategy guide, which is a must btw, tells you) where you can farm/grind and collect points to progress your character early but the game has "caps" so you cant spend days or weeks at the beginning and max out your characters to make the rest of the game easier. It works out pretty well.
The story is well very final fantasyish. Its alot to take in and I have a lot of questions about the story line but Im almost halfway through the story, but not the game. Not sure what that means but the stragety guide emphasizes that so Im assuming once your done with the story then you can further progress your characters somehow. Im not sure how that will play out. The story is good though, just complicated like I said.
The summons are still in the game but dont seem to be as big of a part as before.
Some of the things Im not crazy about are the speed of the fights. You have the option to "auto-fight" or something like that. In other words the AI will pick your actions and this works out very well for the most part. But part of the reason it works so well is you dont have time to manually do it everytime. Its just too fast paced. You have too much to look at and concentrate on. It will be a button masher at first but quickly becomes more. You can go to setting to set fight pace to slow but then it takes forever to do battles.