Rykomatsu of PS3forums and GAF has kindly translated some details concerning WKC, from a Japanese online retailer.
http://gmstar.com/ps3/sirokisi.html
Bulletpoints below
-Gameplay 100hr+∞
A very large scale RPG in addition to the infinite amount of time you can play with friends and partners.
-Attractive casting and immense story.
The thrill of an RPG has been refined with the experience and know-how gained by Level-5 over the years.
-Next-gen quality graphic power
Super graphic scenes output at FullHD 1080p
-Big and small characters fighting alongside eachother to create a chaotic and dynamic battle
With the protagonist being able to transform into the White Knight, dynamic battles with both large and small characters can be created. A direct feel battle system makes unnecessary, any complicated controls, and makes you feel as though you're part of the battle.
-Embarking on an adventure and fighting alongside friends/partners.
Unending infinite gameplay is also included. Via PSN, embark on adventures with friends.