I think the baby boomers will have it better than the next few generations that age after them. Economic growth at it's core is based on population growth (# of consumers), which in turn drives job growth and a skilled labor force. With the retirement of the boomers from the workforce, we are left with a contraction in both general workforce population, and in those with highly specialized skills in the US for the immediate future.
This is already a problem in many specialized engineering and technical industries. There are many unfilled job openings because there are no qualified candidates, and the liability is too high to hire those who are not qualified through either many years experience or PhD level education. I know many engineers (not managers, just regular senior design engineers) who are still working in their 70's and 80's, not because they have to, but because no one is qualified to take their place, so companies are offering generous compensation to work them well past retirement age.
The demand for highly specialized skills will increase and drive wages for those jobs higher (which we will probably fill with educated foreigners), while the majority of the unskilled domestic workforce will have to compete for a decreasing number of service and retail oriented jobs due to the contraction in consumer demand.
US economic growth has been helped by emerging global markets, but the double-digit growth rate of many of those economies (i.e. china & india) has cooled off in the past few years and will approach a more sustainable and terminal growth rate in the coming years. This will be partially offset as other Asian and African countries come out of third world conditions, but they just don't have the population (i.e. consumers) that China and India did.
This may eventually correct itself without some form of global turmoil, but probably not before a couple of decades of stagnant or slightly declining economic growth.
I personally think we're headed down the same road as the Roman Empire. The middle class was fleeced until it eventually fragmented. The financial divide between the Patricians and the Plebs became so great, that the Patricians could basically subsidize the existence of the Plebs, i.e. a welfare state.
Call me crazy, but though the players and technology has changed, I think we just repeat history.