I assume (hope) it would be more like Blizzard's system for Starcraft, which only lets you see the real names of friends that you add using an email address (and if they accept). Showing a person's real name to everyone in game just sounds insane.
This is exactly how the PS4 real name system works. You have to add a friend as a "real name" friend, and they have to add you back with the same permissions. Just adding someone as a friend doesn't grant them permission to see your real name.