AI, and how worried should we be???

So 2 of the 3 " godfathers" of AI have recently quit there jobs , Geoffrey Hinton from Google and professor youshua Bengio from Montreal university ,both warning about the speed of its progress , the threats it poses, and the lack of control ,
We've seen it here already, the place is rife with chat bots all trying to collect personal data, . .be careful who you talk to, .... How worried should we be??? Answers on a postcard please, bots can't monitor that...