Man's intelligence is intimately tied to his physical body. The brain is very finite, cannot be physically extended or copied, takes many years to develop and when it dies the intelligence dies with it. On the other hand, an artificial intelligence is just software. It can be trivially duplicated, copied to a more powerful computer, or possibly a botnet of computers scattered over the web.
It could also adapt and absorb other intelligent software, making any concept of "self" quite hazy. This means that its world view would be very different from man's, and it is difficult to predict how it would behave.
