Hey japhy, what is your intended audience for this work in progress? It's got the right voicing and approach for complete newcomers to programming (and computing?) in general, but I note that some of your vocabulary swings a bit more into territory that expects some knowledge (for example, you mention running your sample 'hello world' program by typing such-and-such, but you never introduced them to the concept of a command prompt.).

Just curious as I am contemplating teaching someone to program who has probably never done more than use a graphical interface, and probably isn't familiar with much more than MS Word and her web browser.