And it *is* easy to support.
It's easy now, when you've got very limited number of users. This will change with widespread application of this format. And to be completely frank with you how easy it is to support the tools for you is comparatively minor part of my concern. After all it's your own decision. The fact remains: someone need to support it. Someone need to test it. Someone need to documents it.
The fact is if one day, quick book is broken and not supported anymore, you just have to use the last correct version to convert your quickbook doc into docbook and work on the doc book.
And what about these:
Do you support quickbook documents validation? Do you plan to invent schema language?
You can run the schema validation on the docbook, it should be easy to find the corresponding part of the quickbook
Do you run unit tests? How flexible is it in comparison with DocBook from extension standpoint?
If you don't fin dit extensible enough, go back to boostbook
Is there a single editor out there that understands this format?
Simple enough to use with lightweight text editor: vim, emacs, kde (someone developed a syntax colorizer for it)
It is very easy to understand, extend and maintain.
First of all it's subjective opinion: I personally don't like these magic char sequences and prefer explicit names in everything. And since you don't have many users yet you can't really state second and third.
For those which don't use xml wisiwig editor, it is useful. If you don't need it, don't use it.
Gennadiy
I just emphasised the point of Matias, that you don't need to use it. And if you start using it, you can easily go back. -- Cédric Venet