The Fact Sheet from the U.S. Treasury states:
The purchases are intended to be residential and commercial mortgage-related assets, which may include mortgage-backed securities and whole loans. The Secretary will have the discretion, in consultation with the Chairman of the Federal Reserve, to purchase other assets, as deemed necessary to effectively stabilize financial markets.
So Paulson, in consultation with Bernanke, could “deem it necessary” to “stabilize” the financial markets by buying boat loads of gold. Or by cornering the market in uranium or platinum.
Or they could decide that they needed to buy Microsoft and Google.
Just like Bush and Cheney have gotten us into oil wars and wars to protect Israel under the guise of being necessary to protect our national defense, Paulson and Bernanke could do anything they want by pretending it is for the stability of the financial markets, especially since no one could challenge their actions in court.