Personally I expect the economy will recover without the magic Obama touch, and surprisingly quickly, i.e. by this time next year we'll probably have started moving in the right direction again....provided Obama doesn't do a bunch of things 'fixing' it that break it worse, like imposing heavy tax burdens to fund his 'recovery' programs.
If such a quick recovery happens, he will probably reap the credit for it, however undeserved, but life isn't fair to Presidents and never has been. Look at Clinton's rep for economic genius, which is based entirely on fortuity and unintended consequences.