This is a fun book to have in the bookshelf, but it has no practical usefulness. In fact, it wasn't even useful in 2002, as a number of commands were missing (tar anyone) and large chunks of the current UNIX market was ignored (DEC OSF/1, HP-UX, etc.). And claiming all operating systems, and not even mentioning OS/400 or OpenVMS is just stupid.

No, this was probably an ego-boost to the involved parties, but I doubt they will go on to greatness, based on this book.