One thing is that machines (robots, computers, whatever) could design systems that would control us (like delivering drugs without asking us) without our consent. That's an enforcement of what I would call a peacful cohabitation... But since we wouldn't even realise... Maybe Matrix wasn't that far on what machines can do. But I think the human race is more dangerous than conscious (all-knowing) machines.
there'll be plenty of opportunity for both laziness and productivity