You read it here first, but Business Week has taken up the story of Why You Will Work Through Retirement. Longer life expectancies, reduced Social Security benefits, a stock market decline, and reduced social safety networks all combine to insure that more Americans are going to work at least part time. Paradoxically, improved health allows workers to be productive longer, while a creaky health care system poses the greatest threat to their retirement security. And, of course, many Americans have saved next to nothing for retirement even though the Boomers are creeping up on their 60s.