I know this all speculative but we are basing this on a theory that Natal 'might' cut into the Wii's marketshare? Natal is doomed because 360's core audience will not support such a thing. Natal is not at all a threat to the Wii. It's more like flattery through obvious mimicry. Same to Arc. LOL!
Things that need to die in 2016: Defeatist attitudes of Nintendo fans