With the Nemesis and legendary gifting systems, does anyone know if it will be restricted to the server region you play on? Or just everyone on your friend list regardless of region? I'm just wondering because I've been adding friends to my PSN from all over the world and it'd be a shame for it to be restricted somehow.
Also do the gifts/Nemesis systems only work for friend playing online at the same time as you? Not sure if anyone knows yet!
I don't know about multiple servers, I figure you should be able to play with anyone on your friend list. As far as I'm aware Blizzard didn't say anything about regional restrictions.
Nemesis should work even if you aren't connected to a multiplayer game. V0mitG0d a resident GAF member has as Review build of the game and explained when one his friends was killed a monster, that monster showed up in his single player campaign.
The monster itself will be marked by "Slayer of "Player ID" as it's name. Each time it kills a player it powers up to a total of 5 times. If the 5th player in a row does not kill it, the Nemesis creature moves on and a 6th player is not invaded.
As for gifts. It also can work in single player. According to V0mitG0d's Stream you will occasionally find legendaries or other rare items automatically assigned to a player on your friend list. You can put these items into your mail box and they will be sent to whoever they are assigned to. From what V0mitGod said, you don't get to pick who the gift goes to.
The last part makes sense as this prevents two players from intentionally tweaking a specific individual on their friend list (Prevents being able to gift yourself rares if you own a secondary PSN / XBL account)
The random nature of gifts means everyone gets something. They just don't know when they get it. But when they do get one it'll truly be a surprise.