Described as the moment, probably the millisecond, that machines get smarter than humans. I feel that just because they will be able to reproduce and have their own society it doesn't mean that they won't want us around. Others mention that with a robo-girlfriend/boyfriend, indistinguishable from the real thing there will no-longer be a desire for humans to reproduce. I say won't people always want babies? they are so cute! Others say that yep, they are cute when they are young but they grow up into truculent teenagers so robo-babies that stay the same age will be a hit. Some people, surely, will want genuine humans?