Also, Sony is the only one who has showcased the working demos of VR+4 player couch coop mix [godzilla in the city, cat vs mouses].
I'm not sure how much of a draw that functionality is going to be. It seems even less likely to be a popular choice than the WiiU's "1 person on the handheld, and the rest on the TV" option.
If they can successfully promote PSVR as a communal thing, they can gain an edge over PC VR solutions.
If we're talking about the mass market draw of communal applications in VR.... Facebook.