Google's AI sounds like a human on the phone -- should we be worried?

It came as a total surprise: the most impressive demonstration at Google's I/O conference yesterday was a phone call to book a haircut. Of course, this was a phone call with a difference. It wasn't made by a human, but by the Google Assistant, which did an uncannily good job of asking the right questions, pausing in the right places, and even throwing in the odd "mmhmm" for realism. The crowd was shocked, but the most impressive thing was that the person on the receiving end of the call didn't seem to suspect they were talking to an AI. It's a huge technological achievement for Google, but it also opens up a Pandora's box of ethical and social challenges.