It's got a lovely world with a great story and excellent music to add to the backdrop. Plus it's a Final Fantasy game but online. I think it comes down to if you are a fan of the franchise, the design of the game, it's stories and classes are all crafted to appeal to the establish Final Fantasy fan, the ability to play one of the legendary Final Fantasy classes like Black Mage or Dragoon is something fans of the series have been looking forward to for a long time; the plot stuff 'Warriors of Light' for example, is a classic FF device http://finalfantasy.wikia.com/wiki/Warriors_of_Light. There is loads I could go into but the 1000 char limit will prevent me giving you anywhere near the kind of detail you're probably looking for.