I think XBO will either tie with the 360, or miss it by very little. It all depends on how big Halo 5 is and how low it drops in the summer months. And while Halo 5 will give it a big boost, mainly in its release month, without last year's fire sale, I don't see the XBO matching 360's 2M holiday season. Maybe not even the Xbox's 1.7M. Not with a (most likely) $299 PS4 to compete with, and maybe a few $249 BF SKUs.