As I understand it, private sites will remain the same as they have been, but in the new public site all users will have the same level of access. So everything's getting flattened out. Additionally, only one administrator can be logged in at a time.
So this new iteration may necessitate a bit more moderation and instruction, but it shouldn't be too big of a deal. Since changes won't take effect until you specifically publish content, you can just require that other administrators not publish their content until you've had the chance to make sure everything's as it should be and in the right location.