What it lacks in content, it makes up for with eye candy.
Sound - The music is quite good. I found myself just idling so I could just listen to the Oerba village theme. SFX also flow smoothly during combat, especially the water spell.
Story - I personally could not connect with any of the characters, except Sazh. The story itself is rather predictable, although the ending made me cry "Bullsh*t!" given that it occurs out of a mere fluke. In terms of the lore of the world, as well as its history, there is very little to see, except for a bunch of ruins, such as Taejin's Tower which is home to a few living statues (you're never told what they are exactly). In other words, the story lacks those tiny details that usually adds to the experience, that you are in a living breathing world. All that's there, is the plot and a bunch of dead guys who couldn't complete their quest.
Gameplay - The entire game is literally spent going from Point A to Point B while killing everything in between. There is almost no interaction what-so-ever with the world around you, save for 100+ dead guys that want you kill something.
In terms of "actual" gameplay, all you have is the battle system, which gets quite repetitious after awhile and the grinding is quite unbearable in the later levels (i.e. 20k EXP for a small health boost). The only time when you're actually given the ability to explore, is around Ch. 10, although I've found that the world is actually quite small. I actually got the feeling that Cocoon was bigger then Pulse, given the extremely limited amount of freedom in this game. On a positive note though, I did find the battles pretty challenging, which is a good step in the right direction. Many of the past games, were pretty easy.
Did I like it? - Yes, to a certain degree. When I went on my 2nd walkthrough, I just couldn't bring myself to keep going after a few hours. Which is sad really, I mainly prefer JRPGs that balance story and gameplay. FFXIII does not however. It's more of a movie then a game.