One of our goals for "dojo Dot Book 0.9" is to make it task-oriented. That way we draw in John Walsh and Laura Allen (http://dojotoolkit.org/dojo-personas), who may not know dojo terminology, but know what they like on existing Web 2.0 sites.
I would caution against taking this too far. Generally web things go through the following phases:
- some cool thing appears on someone's web site
- people try to describe the cool thing to their peers, "it's a combo box that cuts down the number of choices as you type letters"
- someone coins a term so you don't have to describe it each time, as in "incremental Combo Box"
- a developer automates the process of creating incremental Combo Boxes, calling it dijit.IncrementalComboBox.
So now you're writing a book chapter. Do you call the chapter "A Combo Box that Cuts Down the Number of Choices As You Type Letters" or "Incremental Combo Boxes" ? I would opt for the latter, because the terminology is already somewhat established. But where does that leave John Walsh and Laura Allen? We just need to make sure they know what an Incremental Combo Box is, and we can describe that in an introductory portion.
O'Reilly's HTML: The Definitive Guide follows a similar pattern. The first chapter describes a hyperlink. Then a chapter called Hyperlinks tells you all you can do with one.
I believe that task-orientation section headings are less necessary for dijit than dojo. Dijit widgets are more independent of each other, have more self-descriptive names, and shield more details from the programmer than dojo. Explaining widget groups, like Menu or Progress Bar, is the right amount of granularity.
What are the tasks you want to do in dojo? Ajax Patterns (http://ajaxpatterns.org) may be a good starting point. Because each pattern clearly states the underlying problem, "There are too many selections in a common box, making it slow," people can map their own problems to a common term, and then to "dojo Dot Book." Even if this list is incomplete and has irrelevant times, it's easier than answering "what are all the tasks people want to do with dojo?"
Does this make sense?