Thanks for taking the time to read the tutorial and for your suggestions. I've added an example of is now as that is pretty fundamental.
While I do take your point about done_testing it would be very easy for a beginner to miss the last step of reverting to a specific plan at the end and therefore maybe miss that the number of tests is not as expected. As it is documented in full in Test::More anyway I'm not entirely convinced of the benefit of repeating that here.
I'm slightly more minded to mention t as a directory for tests but again if the user is at that level, they're probably looking more at module-writing tutorials where that's covered nicely - and I've already linked to Discipulus's great post on that at the end. Does it need mentioning here still do you think?