Just like we were one of the first O'Reilly books to experiment with using a wiki to get early feedback during the writing process we're also one of the first O'Reilly books to experiment with publishing our material under a Creative Commons license. Starting from today the book is now available here: http://apprenticeship-patterns.labs.oreilly.com/
We're using O'Reilly's experimental Open Feedback Publishing system which lets people, after registering, attach comments to any section of the book. If there's ever a second edition your feedback will be an essential part of it so please don't be shy.