I've done a bit of work in the Nether in the new world, but nothing I can't stand to see go. I can always do it again.
Only thing I worry about is all the supplies I collected just prior to the 1.7 update. Those supplies are stored in the Whammer Dome (thanks for the name, Brad
). Plus, I've collected a lot of new supplies in the new Nether, and hope for enough advance notice that I can relocate those to CC before another reboot.
Otherwise, i haven't been around long enough to be too bothered with the decision. Whatever makes the world fun for everyone is what I support.