I predict that there will probably be something else creeping around in the middle of the year that will come both for xbox and Playstation. Think about it: the expansion will come a year in advance to Ps4 players. Thus, the content is complete. Available. All Bungie needs to do is drop it available to xbox, and same for the House of wolves. I'm sure they have to be working on something right now. Wether that will be available in 2015 ? I don't know. However, think about that lock content in the disc. Their foundations are clearly laid out. Just not available and incomplete, but not incomplete to a point that there is need to begin from scratch.