I'm staying away from Perl 6 books but for a different reason: there's way too much Perl 5 stuff ahead of them on my reading list! From the little I know of Perl 6 it I gather that it will be an extremely cool language, but it will also be a much richer and more sophisticated language than Perl 5, so I don't think it would be entirely premature to start learning about it now, specially the about the more sophisticated new features. That said, there's a fair amount of stuff to read online before hitting the books: the Perl6 FAQ, the Exegeses, the Synopses, the Apocalypses, and TimToady's writeups. There was a thread recently that you may find worth reading.
