How concerned should we be about the rise of artificial intelligences (IE, computers smarter than human beings)? Well, according to some very smart people, real worried!
AIs would not be conditioned by billions of years of evolution to have the same concerns as biological life forms such as ourselves. Their priorities wouldn't necessarily be our priorities. For example, a cold-eyed analysis of oxygen would reveal it to be one of the most corrosive of all elements, behind only chlorine and fluorine, and a logical consequence of that observation for a metallic life form would be that the planet would be better off without it.
Remember that next time you hear that friendly start-up chime.