This time something strange is happening. Job picture seems to be fine. Big conglomerate companies are making huge monies on a global scale. Weak dollars are helping them sell at a competitive pricing. Exports are growing. Definitely, we can conclude that this housing slump is not caused by the traditional factor: Job loss. Is it caused by subprime credit crunch? No, because this slump started in late 2005 and early 2006, long before the subprime became a problem. The subprime issue simply worsened the slump but it was not the cause.
It's also very strange that 20 months after the housing recession, the general economy has been chugging along very fine, only until very recently, it appears that the housing recession is dragging Wall Street into a credit crunch, it potentially trigger the economy into a recession.
As a serious observer, we would like to identify cause and effect. In the past, the cause was always a weakening economy triggering a job loss, then triggering housing slump, like the late 70s, late 80s. The housing recession then was a effect, never a cause. This time around, the order is reversed, housing market got itself into a recession, then triggered a credit crunch, then potentially trigger a recession in general economy (not happened yet). Today, the effect became the cause. That's the weird part of it.
Maybe the housing cycle has a life of its own, like a precise timer, or like an automatic pressure relief valve, it must reset itself to avoid over heating.
Some say it's 1990 all over again. But the cause and effect is entirely reversed. I have a gut feeling that this time, a healthy global economy may come back to benefit US in a surprise way.