I really doubt that a AI would try or even want to destroy us like we see in the many movies that involve AI trying to destroy the human race. If AI was invented it would probably be in it's best interest to work with the human race and not automatically perceive us as a threat. If it does this it could easily gain our trust and then in one foul swoop it could turn us into voluntary pets. Then we suddenly wouldn't be a threat to it any more. That scenario doesn't sound all too bad anyways.
I mentioned this in my recent article on my blog. @digitalcosmos555
I wouldn't want to be an AI's pet though ahaha. The next thing you know, you have robots knocking on your doorstep to "go to your job"