Wii the secondary market dry up?

This past Sunday's business section of the NYTimes had an article by Gretchen Morgenson, "Will Other Mortgage Dominoes Fall?" Interesting piece...she is a good writer who seems to get it. Basically, there is a fear that the issues facing subprime lenders may spread to Alt A, and eventually to the MBS marketplace that gobbles up loans and packages them to investors. The real question is how much of an effect will issues in the Alt A marketplace have on the economy...will default rates hurt investors? Many argues that the traunches that make up these investment vehicles are diversified enough that a higher default rate is not that big of a deal....though Morgenson's piece would beg to differ. Just as important of a question in my humble opinion is: what is going to happen to all of the folks who are legitimate Alt A borrowers...ie, self-employed, or those w/ varying incomes? If the Alt A marketplace dries up, many people who benefited from these loans, and who did not miss payments, are going to have no where to go when they are ready to buy their next property....that's when the real ripple will be felt...Many Alt A borrowers are big income types, who get the pros of an interest only or neg am loan...if they can't find the right loan product, they may not purchase their next property...too bad if we end up throwing the baby out w/ the bath water...