[douglasputnam]

As a teacher I can attest that it's impossible to find decent programming "text books" for Python, PHP, etc for classroom work. Most of the books you see on the bookshelves at Great Big Book Chain may be great books for programming language autodidacts, but they don't get adopted in courses because they universally lack relevant exercises for newbie students.

As a result, instructor's have to create all of the questions and exercises for the course---he/she might as well work without a book. At MIT, the Intro to Programming Course (using Python), doesn't have a textbook because, say the instructors, there are no good textbooks for Python. If Zed can come up with well-paced and instructive questions (Little Schemer-style), he's got a winner.

BTW, If you plan to contribute questions to Zed's book, try to put yourself into a newbie state of total ignorant bliss. Remember that the ideas you take for granted and think of as "simple" are completely daunting to beginners. Pacing is everything.