My favorite economics and business show, Marketplace on NPR, has a great blog video on the continuing financial crisis,
They don't say anything about any criminal behavior but I'm sure that's to-follow. Instead, they seem to be saying that the issue is the lack of reporting requirements, i.e., companies can essentially be gambling enormous sums of money but not need to tell investors that they're doing it. Obviously, a company that reports 'good' earnings but also has to admit that they're doing a lot of CDS 'gambling' won't be viewed as favorably by the market.
Ultimately, I still stand by my earlier post (April 2008) about "The Credit Default Swap scam" -- there's got to be a lot of fraud taking place, same as in other aspects of high finance!