Just to be clear, while we do believe that the soul is the living person, and simply ceases to be upon death, as I have said before we don't believe that it simply ends with that. As Genesis describes, God's original purpose for the earth was for it to be filled with perefct humans that would never see death. That purpose hasn't changed simply because Adam and Eve screwed up. Both James 1:17 and Malachi 3:6 both show that God does not change. Isaiah 45:18 further explains that God did not create the earth simply for nothing, but formed it to be inhabited. We believe the earth and humanity will be returned to that former, pristine state after the wicked are destroyed at armageddon, and many who died will be brought back to life. The future a person has after they die is still very important.
Well that still wouldn't make much sense to me, as to why that would be nullified.
Early in human history, God spoke of his purpose to use a special "seed", a coming ruler, to crush the head of the original serpent, Satan the devil. (Genesis 3:15; Revelation 12:9) This "seed" is progressively identified in the scriptures as Jesus Christ, who reigns with corulers in the Messianic Kingdom. (Daniel 7:27; 1*Corinthians 6:2; Revelation 3:21; 20:6) This is the Kingdom spoken of in John 3:5, a government in the heavens that will vindicate Jehovah's sovereignty and rescue mankind from bondage to sin and death. These men and women put faith in Jesus, who said that they would be "born again" there in John 3:5-7. The apostle Peter described their rebirth at 1 Peter 1:3,4. This new life in heaven becomes possible for them because God resurrects them as he resurected Jesus. (1 Corinthians 15:42-49)
So that verse speaks of those who would be serving in heaven, which we believe is made up of 144,000 individuals. The vast majority will not be included in that group. I have a link to a chapter of a book we publish that discusses our view of baptism and its requirements. (Yes, baptism has requirements! This is why we don't baptize infants, or anyone without sufficient understanding of the Bible.) I do hope this is an adequate explanation.
http://www.watchtower.org/e/bh/article_18.htm