I used OnStar on my trip to Arkansas, this past weekend. It was very helpful and fun to see how quickly I was ticking away the miles on the trip. Plus the ability to call up the remaining miles on the current road, entire trip, and estimated time remaining was really neat. Though, I do agree it can be a bit chatty.
The following is a very close paraphrase of what I heard every time I left the interstate for food, gas, or a pit stop:
You are currently off route. Would you like updated directions? Please say Yes, No, or Cancel Route.
Then I, the driver, simply say: "No," and the voice follows with:
No. OK. Your directions will resume when you return to the planned route. You can return to this menu by pressing the OnStar button. OK. Thank you. Good bye.
It'd be nice if I could at least give an answer before the voice is done speaking. That way I can it her short. And then the voice's response afterward is too long. I can't count how many times I heard it. I'd even shout back at it: "Yes, I KNOW already!" haha. Argh!