Scenario 1: No more money than current budget. End shuttle after next six flights. Extend space station to 2020. End Constellation and pump money into commercial transports of humans to the station. Take whatever is left and begin designing a plan to travel to asteroids and harvest their resources.
Scenario 2: More money than current budget. End shuttle, extend the station. Enable commercial transport. Begin research programs to build a space elevator and design spacecraft to go both the asteroids and Mars.
I really think asteroids are important, especially a place like Ceres, which might even have life on it.
That chat is continuing at http://blogs.chron.com/sciguy/. Launch time is set for 10:59 pm CDT, a bit over an hour from now.