@Chaoswalker: Yeah, maybe. But that would feel like a mismatch to me. I think if Nintendo was going to make a Light Type, they would have done it back in Gen 2, when the Dark Type was introduced.
Plus, it just wouldn't be a good marketing move for Nintendo. Imagine if those games came out today, and White Version had a Light-typed mascot legend while Black Version had a Dark-typed one. You would buy White Version, right? So would I. So would everyone. And then there would be a bunch of unsold Black versions lying around, and a bunch of angry stockholders.
On a different note, am I the only one who was reminded of the lyrics of "Hot N Cold" upon seeing this announcement? In any case, I look forward to the future releases of Pokemon Yes/No, In/Out, and Up/Down. Just hope to God Kate Perry doesn't sue.
@Tortferngatr: What would be wrong with getting old Missingno. back? I look forward to tearing up the Elite Four with my double Water Gun assault.