I think it will be a mixture of the classic grid system and diagonal movement, though I wouldn't mind if the grid system was removed completely. The diagonal movements with the 3DS's slide pad will make for more natural movements and I always thought with d-pad restricts that and makes walking seem unnatural. We don't naturally walk in straight movements and we do make diagonal movements and curves so it makes sense for the character to be able to move freely. Plus the feature of a slide pad is there on the 3DS so why not make use of that technology available? I'll likely have to get used to using a slide pad instead of a d-pad , but I'm all for this change if it happens.