You have to really be impressed with a company that accepts fault and suspends billing until they feel they have done well enough to charge again.
The graphics are unbeatable in today's MMO market. Hands down. Animations are smooth, character mapping is incredible, and I dare you to find a better shot than looking at Ul'dah at night from one of the near by cliffs.
Sound is beautiful. It is not fully voiced acted, but background sound and the few bits that are were done very well.
Combat. This is where I'm sure most will get turned off. Its a return to auto-attack based combat for melee users. Battles are fairly slow in pace, but still offer a lot of excitement.
Crafting. The most rewarding crafting system I have ever had. Crafting being a class allows for a more immersive experience, you take quests for them, and each item needs to be hand crafted. I personally like that.
Class/Jobs. A return of many classic jobs, but with the ability to mix and match some abilities it makes for great customization possibilities.
The world is clearly born in Final Fantasy and it is more than worth your time to play and figure out. It has learning curve so it may not be for everyone, but it has found its way into my permanent rotation.