Yes, it is long awaited and Kirk recently announced that his new book (written with George Neville-Neil) about the design and implementation of the FreeBSD 5.2 Operating System has been finished, and will be ready for sale in early August 2004 (ISBN 0-201-70245-2, Addison-Wesley).

The whole book is divided into five parts: Overview, Process, I/O System, Interprocess Communication and System Operation. The book is considered to be an update to “The Design and Implementation of the 4.4BSD Operating System” published in 1996.

I will be glad if someone can give me a copy of it :-)