I didn't mind the demo, but I agree that it was Castlevania in name and location only. It's got 3D action controls in a 2-ishD environment, and felt like a 2D God of War.
The game itself looks beautiful, and it's not bad by any means. But it would've been way better to have a "normal" Castlevania with the 3DS 3D effect. That really would've popped.