I listen to financial people on news radio pretty frequently, and the general consensus with them seems to be that this money is just a bandaid, and that it doesn't fix the overall/biggest problem GM has, which is the high salary they pay the employees. A company that pays its employees an average of $73 an hour can't compete with companies like Nissan and Toyota who average around $42 an hour. While I know the "financial professionals" are not always correct, this does seem like a valid argument.
http://www.heritage.org/Research/economy/wm2162.cfm