I actually just took a look at the screens there. It appears to be a sort of futuristic/machine world setting.
Yet this quote: "It'll take all the things we loved about Heavenly Sword and make them bigger and better than ever before." would lead you to believe it's actually a HS sequel.
Perhaps he means that they'll take all the design elements of HS that they liked and incorporate them into the new game.
It's all just speculation at this point really...








