http://www.twincities.com/ci_10559948?nclick_check=1

As long predicted by demographers, Baby Boomers are reevaluating their housing needs, transitioning from ownership of large homes with children to smaller places with less maintenance, costs, and the ability to walk away and travel. It's been long expected that they will be selling their larger homes and downsizing to condos and townhouses, and this may indeed be a factor in the slow housing market- too many large homes for sale at the same time to a smaller pool of buyers in that market.