It's an ebook primarily, though we'll publish a paper version once the first edition is done. We keep our Ebooks up to date. For instance, ng-book one has been updated over 30 times in the last two years. We plan to do the same with ng book 2.

I don't know if you've tried to use Angular 2 yet, but the API is still in flux so there are a lot of blog posts that don't work anymore. The examples and sample code in our book, though it's still early, they all work. Email me [email protected] and I'd be glad to give you a free copy to try it out.