An interview with James Lockhart with Dylan Ratigan, who has intimate knowledge of Fannie and Freddie.
1) underwriting standards were lowered due to political demands
2) these government agencies were leveraged at 100-1. (ie. lending money they did not have)
3) Fannie and Freddie are requesting and actively pursuing having banks buy back these bad loans that were fraudulently transferred to Fannie and Freddie (this is really bad for banks).