This is one of the big frictions in the housing market right now. My wife and I would be much more willing to move if we didn't have a huge rapidly depreciating liability on our balance sheet right now. I get why so few home owners are interested in selling out already falling prices.
30-Year Mortgages Are Still a Sweet Deal—For People who Already Have Them
By Doug French
"Government intervened into home mortgages to subsidize home buyers and make home ownership more 'affordable.' As with most interventions, the results have backfired as home prices and mortgage rates skyrocket."