I doubt his anonimity will last long. The buzz of this book is getting to be deafening, despite the fact that it is being published by a relatively obscure publisher.
For instance, "Anonymous" was recently interviewed by Spencer Ackerman for the liberal weblog, Talking Points Memo. This book has gotten a lot of coverage in other well-read weblogs, also.
http://www.talkingpointsmemo.com/archives/week_2004_06_20.php#003082
This is the first I've heard of it. Are you thinking this story is big enough to be on all the news shows and that Rush will be talking about it?
I agree with the comments about the author's anonymity. There's no way it can be kept secret.
One tinfoil question. Is there any way this could be a scam and the author is not what is claimed?