A demo of the title has just been released on the Japanese PlayStation Store. (you'll need a Japanese account in order to download it). Coming in at an entire GB, the demo features a large amount of content and features.
For those who haven't heard of BladeStorm, think Dynasty Warriors in Europe. That's basically it, though its play mechanics vary enough to keep DW fans on their toes.
Bladestorm: The Hundred Years' War is set to hit Western shores during November of this year.