Bill Novelli, the top guy at AARP, wants baby boomers to know they're sitting pretty.

"Your time is now," the 65-year-old CEO said. "Boomers are healthier, wealthier and better educated than their parents. And they have a long life in front of them: Americans turning 50 still have half their adult life ahead."

Novelli also has definite ideas about how boomers - "and their older brothers and sisters, people like me" - should fill those bonus years.

"America has a great need for change," he said. "Boomers can ignite a 21st-century revolution."

Novelli made his remarks while promoting his book, 50+: Igniting a Revolution to Reinvent America ($25, St. Martin's Press). He argues with conventional wisdom that says boomers will tax the system. He believes instead that opportunities for reinvention exist, and that maturity, not academic degrees, will play a crucial role in reforming America.

Novelli fills his book with stories of ordinary people who have made extraordinary changes: Mike Mulligan, who started Angel Flight; Don Schoendorfer, who invented a cheap wheelchair using a plastic lawn chair and began the Free Wheelchair Mission; and Opal Bufford, who started the GAP Limited support group for people raising grandchildren.