On one side, I see that such a book would be usefull, but I think the problems weigh much more than the benefits. On one hand, there are the copyright and quality problems. If you simply reprint posts from perlmonks, you won't have copyright problems (as anyone who posts here already implicitly agreed about the public display of the posts), but you will have clarity and quality problems. If you clean up the posts, clarify the wording etc., you will have much work to do and you will also have to ask each author if you can use his post. Or you have to modify every post so much that it isn't really the post anymore, but then you'd simply be writing yet another Camel book, and there are already enough djihads about Camel books out there.

For KMs opinion, that noone should be allowed to make money from his posts, I think that this mindset is a bit too narrow for me - if someone is able to make money from what I release freely, hey, so be it. I didn't post that stuff to make money, but I'm not restricting anybody else from trying to do so. (I'm more into the real "free" aspect of Perl than the GPL "free" aspect obviously).