Completely, utterly, and totally underrated.
The old-school look fufills the needs of us over-nostalgic gamers. However, it does not slack off in the graphics department. The character artwork is breathtaking, awesomely colored and beautifully inked. The backgrounds are all very aesthetically pleasing. The monsters can be a bit redundant, but short work is made of them with Adol's nifty sword collection.
The music is what really made my ears perk up. When I stepped into Quatera Woods, I fell in love. The butt-kicking synth leads, the kicky beats, everything sounds so great in game. The English voice acting, however, is miserable. Luckily, the cheat room allows you to change it to Japanese, which in contrast is very well done.
The gameplay is just splendid, though the story and goals are a tad weak. You don't really care, though, because it's so fun! The battles go off very smoothly, switching swords and charging them while using items is all very easy. No accidental deaths by pressing the wrong button here! It can be a little tricky getting to bonus areas, and many of the optional quests are useless anyway, but the main game "thread" is just the right difficulty. Not to mention, there are different difficulty levels, and a nice time trial boss battle mode.
In summary, if you want a short, extremely satisfying game, try this. We can only hope the other Ys remakes are released in the US sometime soon.