While bankruptcy is probable, I feel this is not the time to sell, since a large number of shorts have covered and many are waiting for the PPS to drop closer to zero. There is still a slight chance a short squeeze may occur if there is a hint of a possible buyout or workout with the DOE. In any case we may expect a rise in the price even though it is only the result of speculative traders.
While the company has mentioned the possibility of BK, they have not declared it as fact until restructuring or buyout possibilities have been ruled out. Although I think BK is most likely, there is still time for the smoke to clear and make an objective choice after the shock is absorbed.