The fundamental problem with AI is the lack of parallelization. There are more connections in the human brain than there are atoms in the universe.

I am sure someone can write an AI program that is comparable with human intelligence on paper at this moment in time. But, the complexity of the algorithm would probably be exponential, hence massive parallelization is necessary.

I think the ibm blue brain project has the right approach for AI. http://en.wikipedia.org/wiki/Blue_Brain_Project