I do not think the lego option is very serious!

Back to the spec - what should it do, and who’s going to write it?

So the question then is surely this: What features are required of an e-reader application that is switch accessible? Your points 1-9 are more of this rather than document spec specific. You could already hack some of the open source PDF readers out there to do most of this - and yes make it switch accessible. (Actually CHM files spring to mind and the numerous readers that exist).

However saying that, XML is a good starting point if you want to sketch ideas out. My suggestion would be to develop a module for docbook - (i.e. rather like simplifed docbook http://www.docbook.org/schemas/simplified ) which you can build into the document various features. e.g. associated widgits with words, etc. You have to realise though that some, infact many, features need not be in a document spec. e.g. font size, font, colour of text/background, page length, bookmarks, page memory, notes and comments & key access would be defined by the application - not the document. Don’t restrict your users as to how they must read your document - its all about accessibility after all right?!

Don’t go along the route of a new specification - there really is no need. Don’t reinvent the wheel. A XSLT (style sheet that transforms the docbook) into your own accessible format would be all thats required - along with a few bits of programming to convert it to other non-text based formats. e.g. text->speech.

As you say - A PDF reader can be made switch accessible - map arrow keys to your switches. Whats nice about PDF is that it embeds the fonts and is vector based. It runs on all platforms and because the text is in the file you can use text readers. What nags me most about your post is that its very PC (& windows) biased. What about e-readers and other platforms?
Heard about the amazon kindle? http://en.wikipedia.org/wiki/Amazon_Kindle
It strikes me the question isnt so much about “what format?” as to “what device/software do we use?”. Remember - Text is text - you just need to get the software to read the already available formats and present it nicely.

* File Format: if this is an open format other programs can be created to access it. Otherwise you have to stick to a single program or create converters (with possible verse engineering of proprietary formats) You will also probably want batch conversion tools to convert from the source formats. PDF is pretty much an open standard are many tools exist already. There may be Open Source readers that could be modded.

* It may be required to provide other accessibility features as well so compatibility with other AT may be wanted. However that might cause complex interactions and ebooks tend to have highlight and speech options)

* using a new program with builtin switch access may seem to be more controllable but requires all readers to duplicate it or every one to use the same reader. Using a general AT that can control any program (autohotkeys, SAW, GOK, Jambu) allows users choice (but needs an open format too).

So using a standard format with a general AT to control programs should be the most flexible. A new program and format might offer simplified design/maintenance at the expense of user choice and possible lockin.

PS the captcha on this bog doesn’t appear to be accessible to screen reader users (recaptcha is good).

A wonderful dream- a long long way on from the inefficient page-turmers for physical books that we used to struggle to find! Hope it wouldn’t take TOO long?

Seriously though I think that this is reat as some “English” voices cause some difficulties.