Alan - it is not just about themes!
The "Theme" is that Disability Access is a "Fail"!
Disability, and the use of Auxiliary Aids/Services, is not all about Orca and other adaptive technologies. Many people derive no benefit from such technology and don't need it. Some far more basic accessibility issues are being missed and ignored.
I have test driven 12.04 with a number of people who do not need Orca or other specific programs. All they need is the ability to have colour schemes work - high contrast to aide focus due to Neurodiversity - and the ability to make a window fill all available desktop space to aide focus and concentration - and at the same time have access to basic controls such as the Power Button and volume control.
I see that under Unity that the recommended primary route to being able to access modification of the desktop is via the power button to get access to System wide control and "System Settings" - and the very place you need to go is removed if you right click on the desktop and select "High Contrast".?
The lack of accessible routes to report Accessibility Issues and fails from the Beta desktop is also unacceptable - given that all necessary basic functionality has and was present in 10.04 and beyond until now!
The present situation of regressive and not progressive.
From the Canonical website - "Accessibility is cutting edge in software design ".
If this is cutting edge - then someone has missed the bleeding obvious as they cut corners to get an edge. 8^(
Also from the Canonical website:
Accessibility is central to the Ubuntu philosophy. We believe that computing is for everyone regardless of nationality, race, gender or disability. Fully translated into 25 languages, Ubuntu also includes essential assistive technologies, which are, of course, completely free."
That claim is now demonstrably false. It had some accuracy under 10.04 to 11.10 - but now?
When taking simple, basic steps - using well known and basic industry standard steps to improve accessibility, to even test drive a live CD, cause the whole distro to become inaccessible .... ?
That is not just an issue with a high contrast theme - it's far more fundamental and the issue far bigger!
It is not even a single bug - it is far more fundamental.