The first half of the last century was defined by physics, the latter by chemistry. The first part of this century appears to see technological advances at simlar rates on the biological scale. We're still making headway in physics and chemistry, but it's in the fields of genetics, stem cell research and so on where we're doing things that were unthinkable less than two decades ago. Whilst I agree that the problems with AI are more due to a lack of knowledge of how to implement ratherh than a limitation of current technology (i.e. our approach sucks rather than the tech), I believe that our singularity will arrive when we stop having to think about how to translate the carbon wetware to silicon hardware.