Taking into account we are trying to get accessible applications the norm and not the exception, I think is worth to take some actions to help developers to make accessible applications with GNOME technologies. There are several kind of developers we should have in mind:
1) Occasional and newbie programmers: These users need easy to follow instructions with the fundamentals of accessible design and programming.
2) Professional or experienced programmers: I have the impression that, in general terms, these users, unless they were explicitly be told to take care of accessibility issues, don't have too much knowledge about how to address accessibility issues. I think in this case, they can skim introductory material written for newbies, and be able to deal with the rough documentation after that.
3) GNOME developers (=> GNOME designers): Well, possibly developers of this group can be treated the same way that devs from previous groups, but I think that we have to take into account that the role of the designers is getting more and more important. In the early days of the new design approach, it seems that accessibility was considered as an important part of the design process. Check Willie and Máirín posts (I think Máirín's post summarize what designers and developers should check in order to get accessible designs and applications )
I understand that designers have the challenge of producing good designs that work in several formats like netbooks, desktops and tablets and I have the impression they forgot to address accessibility in the process. For example, the new GNOME document application is not navigable with keys. I think designers should consider accessibility in the process and the first stable version of these new designed apps should be accessible.
4) Unity, wxWidgets, Xfce and LXDE developers: Because these projects use GTK+ and other GNOME technologies, they can follow the same documentation and use the same tools for making their apps accessible. Maybe some sort of communication can improve the situation of apps written by users these communities or even we can get some help from them for producing it. Even KDE/Qt users can fall in this group I think.
http://www.wxwidgets.org/docs/tutorials/access.htm (it doesn't mention the a11y capabilities of the GTK+ backend)
Provide easy to use information to get started. We can provide the following formats:
1) 10 minutes tutorial
I think a 10 minutes tutorial can help newbie developers to get awareness of accessibility issues. This can consist in the developing of a straightforward application for presenting the basic of accessibility.
We have the "Smoke testing", but I think is woth a more detailed checklist.
This checklist can count with the collaboration of the design team, and maybe this checklist can adopt the form of a GNOME Human Interface Guidelines or Pattern.
3) Provide the means for getting new GNOME designed apps accessible
The future of GNOME should be accessible and new application should be so and we need the design team to be involved. The commitment of GNOME with accessibility is weakened if brand new applications are not designed to be accessible and we release new not accessible applications.
I personally think they've forgotten accessibility because they are very busy producing designs that work well in the new computing formats like tables, so I think we don't only need to ask for traditional accessibility features like keyboard navigation for old formats like desktop computers, but I think we must encourage the design team to face challenge of adding new accessibility solutions for the new computing formats.
For 2) and 3) I think can be considered to attend to UX Hackfest 2012 in order to address accessibility issues with the designers.