Intelligence without emotion
While I agree that I think there are more immediate threats than AI, there are potential issues with it, like its intrisic lack of emotion. While theoretically, 'intelligence' for want of a better word, feels like it could be programmed based around logic. That's how a large portion of our brains work. But the emotional part which is very much linked to how we think could surely never be programmed without the use of organic material, or at least, an artificially created version of things like hormones.
And without emotion, you have psychopaths. Even if we can't create AI like that, what happens when someone develops a method to upload their conciousness into a machine? Again, devoid of emotion.
That's what worries me about AI. It's inherrant lack of empathy.