Speaking for myself, I've been waiting for 1.0 before using it, but I've been very excited for this project since its announcement. I've personally experienced how much time can be wasted bikeshedding over stylistic issues. In most cases, just picking a consistent standard is far more important than whatever the choice happens to be. Prettier will make almost all that bikeshedding unnecessary.
Even with ESLint having autofix capabilities, Prettier seems far more comprehensive in that regard. It also isn't doing exactly the same things as linters. They check for programming errors as well, not just stylistic issues. With those linters, you also need to decide how to configure the rules (though picking a preset can make that easier).
I have always loved that Python has an "official" style guide (https://www.python.org/dev/peps/pep-0008/), and gofmt (https://golang.org/cmd/gofmt/) is one of the reasons I want to try out Go, so Prettier is a great development in my opinion. I am optimistic that the community will keep on adopting it, helping make our code more readable and allowing us to focus on actually building libraries, tools, applications, etc. rather than arguing over where we should and shouldn't have spaces in our code.
Edit: my TL;DR answer would be that it's a virtually zero configuration way to guarantee stylistic consistency.