It's a really awesome game in my opinion - one of the better things Square has released this gen. There's loads of characters, it's got a good story, the voice acting is great for the most part (Japanese voices are available too), there's a ton of awesome abilities and weapons to find and make, and the Unreal-engine graphics are quite nice. Played almost 300 hours on it so far and still haven't even come close to doing everything.
It's not easy to get into, though. The battle system is complicated, character progression mechanics are unclear, crafting can be a huge ordeal, and there's a mountain of missable stuff. The game fortunately has
an awesomely detailed wiki that renders pretty much all of that moot.
The PC version is loads better than the 360 version (see
this page). The entire game was reworked for the PC, and they added in things like autosave, New Game+, turbo mode for battles, etc. Check it out, it's awesome.