That's a good question - I'm working closely with students who are both skilled and unskilled in programming so that it makes sense to me and to all of them. We're hoping to make the text as straightforward as possible and useful to folks outside of formal classes, but I hesitate to make any promises about what it will and won't deliver before we write the thing. If you have any suggestions, I'm definitely interested in hearing them!
I'm confident that the subsequent versions will get better and better, so if it turns out that there's one part of the book that's hard to understand, we will want to hear about it so that it can be clarified quickly.
We hope to provide a PDF (or similar) version of the textbook on our web site before the physical books ship probably near the end of April if all goes well. This will be freely available to anyone who wants to use it under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported license, as described here: http://creativecommons.org/licenses/by-nc-sa/3.0/deed.en_US
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