It's like a posterchild article about the needs/fears/barriers a convert might have in mind. It's a really helpful article without the usual clichés, which are either
1) helplessly glorifying the Mac
2) helplessly bashing the Mac.
It's truly a good article, and when he's done with his project, this might turn into a really great PDF that should be shared in all the world, Apple should put it up on their own page about converting to the Mac or at least link to the articles.
One thing he does wrong is to tell people they might start with OS 9 and switch to OS X later. (He only does that for a particular reason somewhere.) This is bad, because this further alienises converts. Put them directly to OS X. The apps are there by now, even if you still might have to use one or two of them in Classic.
This is especially important, because the Mac's big appeal for Windows and UN*X users alike is now Mac OS X. Not only the good look, but the power and the interface. For Win/UN*X users Mac OS X is *exactly* what it's not for OS 9 users: The perfect GUI, they've been longing for.