In regards to the book's online version, I like how it has code examples that one can edit and run inline among the book's text. I often find myself, while reading a book on a particular language, opening up a new project in an IDE or a REPL in order to fiddle around with what the book it trying to teach. This makes it much more fluid. It was a pleasant surprise. It is a nice concept I have not previously seen done.…
I just wish we had hi-res, color, e-ink monitors with quick refresh rate. I can't bring myself to read an entire book online; even if it's free.
For what it's worth, some people have hacked around with the Kindle to try to make this a reality, but as you say, the refresh rate is the bottleneck. [1]