No matter what is observed, creation will not be disproved. But nothing ever seems to disprove evolution, either, despite a much narrow range of observations consistent with it. If there was a designer, he seems to have mimicked the action of evolution to a T.
The biggest problem with most potential disproofs of evolution is that we should have noticed them by now. Had they been as abundant as Cs claim them to be, evolution would never have been proposed in the first place.
Well, you got Behe now and irreducible complexity. It very well turn out that he's a fraud (although I think that would have been well established by now)
More likely it will mean science getting off center and forcing itself to face the questions Behe is bringing up and improving our understanding of the world around us with an improved evolutionary theory.
Or, just as possibly, it might mean throwing out macro-evolution all together.