I had heard about this film years ago under it's original title "Wonderful Days" and kept an eye on it waiting ages for it's UK release. For the English speaking market the title changed to Sky Blue for some silly reason. It was released in UK cinema's but it must have been a select few screens - none of my locals were showing it!
I was patient enough to wait for the fully fledged UK DVD release. The movie was re-editied and given a new soundtrack for the English speaking audience. A fine job done, too!
The other reviews are correct - this film looks absolutely fantastic. The option of using a hybrid of 3D and 2D animation works a treat. It's taken something like 5 to 7 years to produce this movie. Time well spent in the beauty department!
The plot on the other hand starts off quite promising, building pretty well, but the ending is somewhat disappointing. It left me feeling quite empty, as the film hadn't really explained why the characters took the actions they did in the films climax.
I felt a little bemused, wondering if production funds were cut short causing a sudden need to hurridly end film-making, or whether it the Korean's were creating a typically Japanese climax causing you to think long after the movie credits rolled by. (If it's the latter, they failed miserably.)
Fans of animated flicks will enjoy and drool over the visuals, probably not caring too much for the plot, and loving it all the way through. The standard film buff will probably be disappointed by the weak plot and not care too much for the animation style, classing it as eye candy. As mentioned the animation is flawless, but the plot obviously holds it all together - it does do this well until 2/3's of the way through where things crumble somewhat.
In my honest opinion, this is probably just a suitable purchase for animations fans. It's nowhere near as good as Akira (plot is weaker, but it potentially looks far greater), but it's is definitely no weaker than Final Fantasy: The Spirits Within.
The average film buff would get bored and probably only watch it once and forget about it, prefering to stick with Disney.
Depending on which category you fall into, I think I've given you a straight answer.
Having said that the Korean's have done a great job but let themslves down with the ending. However, they should definitely do something again as they truly could take the reign from Japan! I look forward to checking that potential soon!