O'Reilly book on Twisted

[Steve M]

Does anybody know:

Is this book fully up to date with Twisted 2.0?

Does the book cover Nevow at all?

Does the book cover general programming concepts related to
concurrency? I'm reminded of those high quality articles about
Deferreds and event programming by one of the Twisted developers?

What is the relationship between the primary developers of Twisted and
the book?