I'll go wherever the people in the game want to. I don't play my Luministi character(s?) anywhere else, so for me it makes sense to stay on LJ because I lose paid options and icons otherwise. But I'm sure that's not the case for the majority, so I would say do whatever's necessary to keep the game going as before. I'm not sure how mirror sites would work, but so far I get the impression that everyone would be willing to stay or move as decided, so it seems like it wouldn't be necessary?