A friend of mine does a Minecraft podcast for TheShaft and he said that they moved to a new world once and that everyone raised a holler so they put in a portal to the old world... but the funny thing was that hardly anyone went back to the old world afterward.
As someone who has NOT contributed a major structure to the world it's easy for me to say let's start over (which would be my vote), but I think it could be pretty exciting. A lot of us weren't around for the pioneer phase of this world, so we hunger to become founders
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