The two remaining investment banks (MS and Goldman) are now structured as bank holding companies. Thus all the big finance firms are now essentially commercial banks. This is the situation that existed before the Great Depression. The Glass-Steagal Act (enacted after the stock market crash in 1929) was designed specifically to separate investment banks from commercial banks, but was repealed in 1999. Repealing Glass-Steagal is generally credited as part and parcel of the deregulation that created the current crisis. Interestingly as far as regulatory and legal matters are concerned we are jumping back about 90 years to the situation in the 1920s. It remains to be seen if Congress will enact regulatory changes that would create incentives for banks to restructure in a different legal framework.