The high cost of jumbo mortgages

"The rates on jumbo mortgages spiked this summer to as much as 1 percentage point above non-jumbo, or so-called conforming, mortgages. While the difference in rates narrowed a bit in the fall, it has widened in recent weeks, once again approaching a 1 percentage point spread. As of Dec. 28, the rate on a 30-year fixed-rate jumbo loan was 7.09 percent, while the rate on a comparable conforming loan was 6.29 percent."