I bought it last week, have clocked probably 27 hours into it, as well as a fulltime job and a girlfriend (who hates me playing games too much). So that should say something.
The battle system is VERY complex, even when compared to other JPRGs, and there are a number of factors that need to be considered and taken into account for every attack, else you'll find yourself in a very tight spot. Still, very rewarding when you figure out the best ways to deal with your enemies.
Story wise, it seems to start off very slow, only really giving you enough information at the start to know why your characters (the three on the box art) are doing what they're doing, and a semi-plausible reason for the world map to be shaped the way it is (world was ending, so the remnants of humanity built a gigantic tower which coud support life when Earth now couldn't). After 27 hours of play (admittedly a lot of just wandering/grinding/looking for the one item I needed to finish a sidequest, when they disappear if uncompleted after finishing an ingame chapter) its finally giving a reason for the characters to be involved in a storyline larger than themselves.
Characters are as plausible as the world they live in, although maybe not their abilities. I'd like to see someone shoot a target from the ground up into the air, then leap over it and shoot it some more, slamming it into the ground. Quite acrobatic, and makes the battles interesting to watch, but you don't play JRPGs for realism now, do you.
Graphically, 8/10 – the gears of the tower all move in both the major cities and the world map, characters are fluidly animated and well detailed – even the alternate costumes (which are customisable, but not a lot of point to it).
Soundtrack is rather good – two tracks available from the website to preview, all quite orchestral, never seeming to miss a beat as far as the emotions in each scene are concerned.
Apologies for length, Steve