How can this even be a serious question? We don't even know what the Holiday lineup will be, let alone the consumer response to that lineup. Most of these questions are typically just "which console are you the biggest fan of" but this one is nothing but that.
So I guess I'll just say...Nintendo. Haha...I've got nothing to go on but it still feels good to root for your team, right?
Eh, there's nothing wrong with speculating. No different than 'how much will 'x' game sell'. It's fun to look forward (especially since we're on a site that tracks numbers).