There are only pins on the bottom according to who leaked the pictures, but the opening is symmetrical like you say and the male part of the equation has contacts on both sides, which indicates it'll work inserted either way.
Yeah that was the reason why I thought it wouldn't work either way. However, I didn't think about the cable
The cable might have connections on both sides, meaning it can be entered in either way I hope that is the case...
One thing on these new dock connector parts is that there isn't a small metallic ring around (Which suggested to me some sort of magnetic lock, as per MagSafe)