I think AI almost always provides fertile ground for discussion of human nature. Usually science fiction goes the "Star Trek's Data" or "Short Circuit" route, where a lightning bolt here or a special chip there can create real emotion and self-awareness. The implication, intentional or not, is that humans are nothing more than "meat-machines", with no intangible (spiritual) nature, since their defining characteristics can be reproduced exclusively in the physical realm.
Although sometimes sci-fi supports a non-naturalistic view. Such as the recent Battlestar Galactica (in which the Cylons are made by humans but implanted with souls by "God") or Terminator: Salvation (and the Sarah Connor Chronicles, R.I.P.) which argue for the idea that machines, no matter how intelligent, cannot gain true self-awareness.
Would you guys agree that AI concepts always fall into one of these categories, or is there another way you've seen it used in fiction? Maybe we could try listing uses of the AI concept in fiction and categorizing them as supporting either a Naturalistic or Supernatural view of humanity?
For example, I think Naturalistic examples of AI include:
Data (Star Trek TNG)
Johnny 5 (Short Circuit)
"The Doctor" (Star Trek Voyager)
Agent Smith (and most other machines/programs) The Matrix
The programs and the new life form chick from "Tron: Legacy"
Supernatural supporters would include:
The Terminator franchise
AIA (Spirit Blade: Dark Ritual, shameless plug)
Any thoughts or examples to add?