Author here!

You can check out the new book here: http://rust-lang.github.io/book/

We're working on the new book because the old book isn't as good as it could be, but that doesn't mean it's bad: a lot of people have told me that they really love it. But I am hyper-critical of my own work, and there's a lot of ways you can improve something that's already good :)

As you can see, the new book isn't really far enough along to fully teach you Rust yet. I would maybe check out the new material first, and then just read the existing book afterwards.