Joel,
You asked, "Whose gonna live on the new earth then?"
I believe your question springs from the Watchtower Society's teaching that God will soon kill everyone on earth except true Christians. Fortunately, the Bible does not teach that. I believe that when Christ returns He will judge only the Christian world. Two-thirds of the earth's population has never even heard the good news of Jesus Christ, including billions of people in lands like China and India. The Watchtower Society teaches that God will soon kill all of these people. I think they are wrong. This does not sound like the God of love, justice and mercy I worship.
One thing that leads me to believe this is an incorrect understanding of scripture is that that the Bible tells us that "Judgment begins with the house of God." (1 Peter 4:17) Jesus also said those who will rule as kings with Him will "judge the 12 tribes of Israel." (Luke 22:30) To me this indicates that when Christ returns and draws all true Christians to Himself (Matt. 24:31), they will then determine who among those who have heard the good news of Jesus Christ and not taken it to heart are deserving of death. "The 12 tribes of Israel," spoken of in Luke 22:30, I believe refers to all those who have heard the good news preached by those whom Galatians 6:16 calls "the Israel of God." Remember, the literal "12 tribes of Israel" had all heard the Law of Moses, but few had taken it to heart.
Remember too that it was only the city of Jerusalem that was destroyed in 70 AD, not the entire Roman empire, after those in Jerusalem who heeded Christ's words of warning had escaped. And First Century Jerusalem has long been understood to picture the Christian world, or as Jehovah's Witnesses call it, "Christendom."
Also to be considered is a fact known by most serious students of the Bible, history and science. The flood of Noah's day was a local event, not a global one. God brought that judgment only upon a land that had heard the message of "Noah, a preacher of righteousness," and failed to respond to it. (2 Pet. 2:5) God did not take the lives of those in other parts of then widely populated earth who had not heard Noah's preaching.
Interestingly, Revelation chapters 8 and 9 talk quite a bit about "a third of the world" being judged. And by population, the part of the world claiming Christianity as its religion is almost exactly one-third. (See The World Almanac 1998, page 654)
If this understanding is correct, that Christ is returning to judge only the Christian world, then Christians, who all have the same "one hope," will then have plenty of people to rule over as they serve as kings with Christ for 1,000 years. And they will also then have plenty of people to help come to know the true God as they serve as His "priests." For that is, after all, what priests do.
The Bible does not tell us exactly what will happen in the future. Because it does not, the beliefs of Jehovah's Witnesses and my beliefs on this subject matter, which I have just presented, can only be considered speculation. However, I believe that Jehovah's Witnesses should be made aware that there are other ways to understand God's clearly stated intentions to have the meek inherit the earth (Ps. 37:11), and His intentions to have all Christians rule with Christ for 1,000 years, than to change the good news preached by the apostles which offered the same "one hope" to all Christians. (Eph.4:4-6; Gal.1:8,9)
"For the message of the cross is foolishness to those who are perishing, but to us who are being saved it is the power of God."
(1 Cor. 1:18)
Mike