Jason Snell, writing for Macworld:

It strikes me that Siri could be a much better assistant to people who are driving their cars. CarPlay is a nice idea, but far more people have Bluetooth audio in their cars than have CarPlay. It’s unsafe to look at an iPhone screen while you’re driving, but Siri can theoretically replace that need. It performs some basic capabilities now — reading recent text messages when you ask, for example — but too much of what it offers requires you to look at the screen. (Siri should also be much more wordy when it knows I’m driving, including offering to read the text of notifications I receive and providing a more interactive interface for processing lists of information.)

This whole article was interesting, but this bit about Siri, CarPlay and the problem of translating information into an audio response for screenless folks really clicked for me.

I think rote reading of a screenful of data is not necessarily the best approach. As Siri gets smarter about the data that flows through it, Siri can also learn a set of ways to summarize that data.

Instead of reading a screenful of weather data, Siri could just say Sunny and 81°, then allow you to ask a follow up question.