It is indeed and it is a lot of fun too. I've been playing it since BETA and still loving it.
They've brought in a lot of cool stuff with it, of course you've got the job system (current jobs: Warrior, Paladin, Monk, Ninja, Dragoon, White Mage, Black Mage, Summoner, Scholar, Bard, Dark Knight, Astrologian (like a Time Mage) and Mechanist). You've also got big fights with loads of the summons from the series, referred to as the Primals, so Ifrit, Shiva, Ramuh, Leviathan, King Mog, Garuda, Titan and in the expansion they've added Bismarck and made up new one, Ravana (who I beat the other day) and have intentions of adding more in the updates to come. They keep the game regularly updated with new content. We've now got chocobo racing, triple triad, golden saucer, housing, chocobo breeding, flying chocobos, airship building & ventures and the loyalty rewards aren't so bad either. For example, that cloud strife set there is a loyalty reward.
I mean, there's areas I would still improve the game, but it is a great game and does a lot right that other MMO's don't, for example, it is really friendly in design to new players and you don't actually feel like you want to grind. I am enjoying the casual stroll through level 50 to 60 in the new expansion and not getting bored of it.
They also make the content challenging and caters both to casual and hard core players, as testament, through out the pre-expansion content, they had 2 sets of end-game raids going, The Crystal Tower (yep, FFIII reference) which caters to more casual players and also The Binding Coil of Bahamut, which is the much more challenging set of raids that ends on...defeating Bahamut. Sound track is good in places, but in the new expansion, Nobuo has had a much bigger influence in it. And the areas in the game in general look amazing and they've done really well with the atmosphere of places, especially in the expansion.