It covers Rust 1.17. It is almost entirely still accurate; you’d need to set the edition back to 2015 in your Cargo.toml for some examples to work, but the foundations are still very solid. You’d have to adjust some import paths to get them to work in Rust 2018 thanks to the module system improvements. It won’t tell you about new features, but the big picture is still fully accurate, you might just need to tweak some details, and read some newer release notes to learn about some new things. It’s still a great book.