First of all, the link referred by patrick.net gives very informative charts on securitized mortgage and other real estate and mortgage related materials. It is worth viewing.
I am not an expert in mortgage area and would like to validate my point. When you look at exhibit 5 of the link. Government, Fannie and Freddie, and commercial banks, which make up to 41% of the market shares, are important buyers of the mortgages. Other more influential buyers are foreign investors and others. Although we are seeing subprime problem and problems of Bears and Sterns, etc that slightly affect the performance of the stock market. Now if government, Fannie and Freddie, and the banks insist not to sell the product no matter how bad the mortgage performs, the securitized market will not slide.
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