The latest patch, 3.3.5 "Ruby Sanctum", includes the new RealID feature.
This feature allows you to add IRL friends, which shows you their RL name
and allows cross-realm chat, status and such other features. HOWEVER, it
ALSO includes ANY of their friends to see YOUR RL name.
I just want to remind you to keep this in mind if you choose to use this
optional feature! Be very careful who you add to the RealID list, for their
friends will also see you (and vice versa).
SoD forum topic for this.