It sounds much easier to me for Facebook to pay a random developer to develop something like Home to get people on board as it is easy for Sony to have something like Home (just read few days ago that the devs who made Home want to make something new) and get Facebook users away from the Facebook "virtual world" to Sony's virtual world.
Facebook doesn't even need an own team for that, just give another company some money to create this world.
I'm btw one of the guys who think VR will have a bright future. Not sure when but the time will come when as example people in nursing homes will sit with such a headset in their room to experience something like walking though a museum instead of lying in the bed and looking on the ceiling the whole freaking day or like one million other things it will be used for....
