I just saw Jeff Hawkins give a talk and it was quite interesting. I was a bit worried, however, that he is basing his theory of intelligence on the human neocortex, while claiming to go after general principles.

This is guaranteed not to be terribly general, considering the many bits of matter on this planet that exhibit intelligence without a neocortex. By many, I mean ones that hugely outnumber humans.

So very interesting stuff, but not the answer that I think he wants it to be.