Multiple connected instances, so much closer to EVE than WoW.
Or, maybe a better comparison is that it's like DayZ, only instead of picking a server manually, the matchmaking server drops you into an instance automatically.
If you have friends on your list, it tries to put you in the same instance that they are if you're in the same system.
All traffic is peer to peer? Hmm... won't that open the door for abuse if there's no server instance to soundcheck results?As above, the match making server deals with grouping players together to give the best experience.
Players are grouped based on various factors, being a friend with another player increases the probability of being paired up with them.
All network traffic related to seeing other players in close proximity (e.g. combat) is peer to peer to give the lowest latency.