I'd like to start first with a basic premise of this discussion which is: does cross server LFD lead to less developed communities and less emergent gameplay? From my experience the answer to this first question is quite clearly yes becuase it effects the community both in and outside of dungeons. - Knowing you will almost certianly never see the players you are playing with again there is no incentive to socialise. - Knowing you are unlikley to do dungeons with people you see in the "world" there is less incentive to strike up conversations and cooperate while questing. - Now that you do not have any meaningful repeat interactions with other players the game has no context and by extention your progress in the game is essentially meaningless. Now one thing that has been brought up is: "but I can add people (X-server and native server) to a friends list and in that way develop relationships". My response would be that this does absolutely nothing to build a sense of community across the server or create emergent gameplay. The server is now just segmented into small groups of friends. The point of an MMO should be repeat interactions with other players which enrich the world. It is not solely about making friends - is about giving the world context. The second question is: Do the benefits of X-realm LFG outweigh the costs to the community? In the interests of not making this post too long I won't go into these arguments. My overally point though (and maybe this is obvious) is that it think its pretty clear that if your only goal was to create a great community you would absolutely not implement a X-Realm LFD tool. The debate is about the extent to which you sacrifice the community and sense of belonging to a world to decrease que times. In my opinion MMOs continue to get this balance wrong, resulting in shallow games that cannot hold long term subscribers.