Excerpt: Baby boomers are rethinking retirement as they watch their investments dwindle. Plummeting home values, fading 401(k) accounts, shrinking interest on CDs and worries about their own jobs are driving the trend. Fears about the future of Social Security and defined-benefit pensions only add to anxiety for the over-50 set. 'Even people who are five years away from retirement are nervous,' .... More than half of people surveyed in an Associated Press-GfK poll released last week said they worry they'll have to work longer because the value of their retirement savings has declined.  MORE >>