Over time, the list of securities eligible for the TALF is expected to expand to include additional securities, such as commercial mortgages, as well as securities that are not newly issued. Relative to the Fed's short-term lending to financial institutions, the CPFF and the TALF are rather unconventional programs for a central bank to undertake.
I see them as justified by the extraordinary circumstances in which we find ourselves and by the need for central bank lending practices to reflect the evolution of financial markets; after all, a few decades ago securitization markets barely existed. Notably, other central banks around the world have shown increasing interest in similar programs as they address the credit strains in their own countries.