The great hockey player Wayne Gretzky was famous for his reputation for not skating where the puck was -- but where the puck would be. Will builders be as adept at predicting where their future buyers will want to be?

A llegra Calder, a researcher at Harvard Joint Center for Housing Studies, suggests there are plenty of clues to help builders. Most notably, she contends, the Hispanic population will be driving housing demands in the next 10 years. Houses where several generations live tend to be structured differently than the standard American home, she says. "A two- or three-bedroom home won't do it for them," she says. "They tend to become homeowners later in life, and culturally it is much more normal to live with their mother-in-law." California builders, she adds, "are starting to realize that."

Don't count out the rental market, says Calder. One trend she's seen is that people are moving from owning to renting at different stages of their lives -- divorce, for example, can create renters where there were none before. People move for work -- changing jobs an average of seven times during the course of their career in this country, she notes -- and sometimes they rent before they buy in a new city, to get to know their new surroundings. "People are obviously moving around more," she says, "and are not averse to renting for a year before buying."