I only picked this up recently, its unfortunate release, almost simultaneous with the highly disappointing FF13 meant that for anyone other then hardcore fans of the genre this title went unseen. A what a shame because this is the far superior game.
Explaining why this game is so good is actually quite difficult. The combat system is the standout feature of this game, while I don't think its quite as complicated as some reviews I've seen imply, it has plenty of depth, and requires skill and tactical thinking in such a way as to make the turn based combat feel immersive, rewarding and somewhat frantic. The difficulty of the combat is offset by the fairly lenient retry system, which allows you to restart the fight at the cost of a small amount of in-game currency.
What else is there in this game? The between dungeon transversal is performed with the aid of 'energy hexes' which unlock hexagons on the word grid. This is a nice touch and adds a light layer of puzzle solving. Another area of puzzle solving is the weapon customisation, see here:
http://eoe.wikiwiki.jp/?%A5%AB%A5%B9%A5%BF%A5%DE%A5%A4%A5%BA%CE%E3
Its addictive and fun, as well as slightly silly. In a good way.
The story is a bit slow, but adequate, a word which also describes the graphics (the dungeons are very grey!).
Overall, great fun, a must for JRPG fans.