All of it. All the way up to the C-Suite.
This would naturally improve efficiency, and in not a few cases it would probably apply a significant multiplier to overall profitability.
That doesn't mean it would be a good idea politically or socially - although depending on the value system and long-term strategic insight of the AI, it might be an improvement there too.
You could even have an automated YC, where a model of Paul Graham selects between different business models produced by a selection of AI agents.
This could just be a joke, but to be honest I'm not completely sure it's not a serious prediction.
For this specific example, I haven't been following AI that much, but from the news it doesn't seem to be advancing that far. Sure, we have self-driving cars, but a whole team went into creating them, and before that there were teams involved in image recognition, mapping, navigation, engineering, and more. Natural language processing has advanced pretty far though, I'll give you that. But there's a lot of stuff that happens in between the query "Siri, what's the Weather?" and the response and people will need to be involved in the processes in between.
But with advances in both hardware (3d memory, memresistors, neural network chips, graphite), and software(recent advances in CV, statistics, deep neural networks) that point is moving forward all the time.
Not too long ago we couldn't imagine that a computer could recognise house numbers and streets names in arbitrary fonts, but that is what powers google maps. Luckily in this case the technology has not replaced a huge workforce of would-be google-mappers. But that doesn't mean that it can't be done.
Technology, and especially AI has the potential to be enormously disruptive. And even if the risk seems remote, it's too big to ignore imo.
HN seems to be stuck on some singularity, but personally I just think it's a byproduct of futurology. Just look at the past and how they envisioned the future. Heck, we can study the industrial revolution and the reaction of Luddites, but people still have jobs today. Like I said, we might just have to move an abstraction higher, just like how we went from manual labor, to controlling machines that do manual labor.
Also, just a nitpick but all that google maps OCR was done by humans via Captcha.
And for how long do you think that job may be safe from automation?